M100 TS-DOS ROM RST 7 Handlers
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TS-DOS Model 100/102 ROM RST 7 Handlers
This is the code for the DOS-ON RST 7 Hooks, along with the TPDD1 Rename functionality.
; =========================================================================================
; Load default RST 7 vector table values
; =========================================================================================
3FFAH LXI 7FF3H ; Address of a RET opcode in ROM
3FFDH SHLD FAE6H ; Save as hook for RST 7,0Ch?? We didn't modify this one
4000H SHLD FB08H ; Save as hook for RST 7,2Eh - DSKI$ function
4003H SHLD FB0AH ; Save as hook for RST 7,30h - OPEN/CLOSE/PRINT/LINE INPUT
4006H SHLD FAF0H ; Save as hook for RST 7,16h - SAVE
4009H SHLD FAF4H ; Save as hook for RST 7,1Ah - RUN
400CH LXI H,08DBH ; Load address of "Generate FC Error" in Main ROM
400FH SHLD FB2CH ; Save as hook for RST 7,52h - LFILES
4012H SHLD FB32H ; Save as hook for RST 7,58h - KILL
4015H SHLD FB34H ; Save as hook for RST 7,5Ah - NAME
4018H SHLD FB36H ; Save as hook for RST 7,5Ch - SAVEM
401BH SHLD FB38H ; Save as hook for RST 7,5Eh - LOADM and RUNM
401EH RET
; =========================================================================================
; Install our RST 7 hook for all RST 7 calls we are interested in. This uses the "ON TIME"
; time storage location to copy a 6-byte routine to switch to OptROM and call our
; RST 7 "switch" statement in our ROM. This means ON TIME can't be used when using
; the DOS-ON feature.
; =========================================================================================
401FH CALL 3FFAH ; Load default RST 7 vector table values
4022H LXI H,4084H ; Point to RST 7 RAM hook routine
4025H LXI D,F93DH ; Point Time for ON TIME interrupt to use as our hook routine
4028H LXI B,0006H ; Copy our RST 7 hood to the "ON TIME" time location
402BH CALL 4A05H ; Move BC bytes from HL to DE - copy our hook to RAM
402EH LXI H,F93DH ; Load address of "ON TIM" time where our hook was copied
4031H SHLD FAF4H ; Use our RAM RST 7 Hook for RST 7,1Ah - RUN
4034H SHLD FAF0H ; Use our RAM RST 7 Hook for RST 7,16h - SAVE
4037H SHLD FB38H ; Use our RAM RST 7 Hook for RST 7,5Eh - LOADM and RUNM
403AH SHLD FB36H ; Use our RAM RST 7 Hook for RST 7,5Ch - SAVEM
403DH SHLD FB08H ; Use our RAM RST 7 Hook for RST 7,2Eh - DSKI$
4040H SHLD FB0AH ; Use our RAM RST 7 Hook for RST 7,30h - OPEN/CLOSE/PRINT/INPUT
4043H SHLD FB2CH ; Use our RAM RST 7 Hook for RST 7,52h - LFILES
4046H SHLD FB32H ; Use our RAM RST 7 Hook for RST 7,58h - KILL
4049H SHLD FB34H ; Use our RAM RST 7 Hook for RST 7,5Ah - NAME
404CH RET
; =========================================================================================
; Process jump to custom RST 7 Hook routine from Main ROM
; =========================================================================================
404DH PUSH PSW ; Preserve PSW
404EH LDA FAC9H ; Get address of last RST 38H call argument
4051H CPI 1AH ; RST 7,1Ah Hook - RUN statement
4053H JZ 4451H
4056H CPI 16H ; RST 7,16h Hook - SAVE statement
4058H JZ 44E7H
405BH CPI 5EH ; RST 7,5Eh Hook - LOADM and RUNM statement
405DH JZ 43C1H
4060H CPI 5CH ; RST 7,5Ch Hook - SAVEM statement
4062H JZ 440DH
4065H CPI 2EH ; RST 7,2Eh Hook - DSKI$ function
4067H JZ 4324H
406AH CPI 30H ; RST 7,30h Hook - OPEN/CLOSE/PRINT/LINE INPUT satement
406CH JZ 451DH
406FH CPI 52H ; RST 7,52h Hook - LFILES
4071H JZ 4346H
4074H CPI 58H ; RST 7,58h Hook - KILL
4076H JZ 4377H
4079H CPI 5AH ; RST 7,5Ah Hook - NAME statement
407BH JZ 4396H
407EH POP PSW ; Restore stack frame
407FH MVI E,02H ; Prepare to generate "SN" error
4081H JMP 4C37H ; Generate error in E
; =========================================================================================
; RST 7 Handler copied to RAM for DOS-ON
; =========================================================================================
4084H CALL FAA4H ; Call RAM hook to switch to OptROM
4087H JMP 404DH ; Jump to TS-DOS RST 7 handler in OptROM
; =========================================================================================
; Open TPDD file for Read Mode. File already stored in TX buffer.
; =========================================================================================
408AH LXI H,0101H ; Load "Open file" opcode
408DH MVI A,03H ; Load OPEN_READ mode into A
408FH STA FCE8H ; Save A in TX data storage (mode location)
4092H JMP 409BH ; Send Request in HL and await response - Open File
; =========================================================================================
; Send TPDD Write File opcode using RX buffer with length in A
; =========================================================================================
4095H MOV H,A ; Move length to H
4096H MVI L,04H ; Load TPDD_WRITE opcode to L
4098H JMP 40A7H ; Send TX packet using RX buffer
; =========================================================================================
; Send Request in HL and await response
; =========================================================================================
409BH CALL 4822H ; Send TPDD Command/Len in HL
409EH CALL 49F0H ; Wait for data to be ready
40A1H CALL 47CCH ; Copy Receive RX packet routine to RAM and execute it
40A4H JMP 47F8H ; Check RX packet for Normal Response & report errors
; =========================================================================================
; Use RX buffer to send a TX packet (used to send data). Opcode/len in HL
; =========================================================================================
40A7H SHLD FD02H ; Save Opcode/len to RX buffer
40AAH LXI H,FD02H ; Storage for RX packet
40ADH CALL 4828H ; Send TPDD pointed to by HL
40B0H CALL 47CCH ; Receive a packet
40B3H JMP 47F8H ; Check RX packet for Normal Response & report errors
; =========================================================================================
; Send TPDD_READ data opcode and recieve response
; =========================================================================================
40B6H LXI H,0003H ; Load TPDD_READ opcode
40B9H CALL 4822H ; Send TPDD Command/Len in HL
40BCH CALL 47CCH ; Receive a packet
40BFH LDA FD03H ; Get length byte from RX buffer
40C2H LXI H,FD04H ; Point to return data addres in RX buffer
40C5H CPI 80H ; Test for maximum read length
40C7H RET
; =========================================================================================
; Write HL bytes of data from (DE) to TPDD
; =========================================================================================
40C8H PUSH D ; Push address of write-data to stack
40C9H PUSH H ; Push length of data to the stack
40CAH CALL 4101H ; Test free Disk space and issue TPDD_OPEN request
40CDH POP H ; Get address of data from stack
40CEH SHLD FCD5H ; Save length as remaining length to write
40D1H POP H ; Get address of data to write to TPDD from stack
40D2H LXI D,FD04H ; Point to RX buffer to copy write data
40D5H LXI B,0080H ; Prepare to copy 128 bytes of data to the RX buffer
; =========================================================================================
; Write BC bytes of data from (HL) to (DE) and write to TPDD, DE=RX buffer data pointer
; =========================================================================================
40D8H CALL 4A05H ; Move BC bytes from M to (DE) with increment
40DBH PUSH H ; Push the updated address to the stack
40DCH LHLD FCD5H ; Get the remaining lenth left to write
40DFH LXI B,0080H ; Prepare to subtract 128 from the length
40E2H DSUB ; Subtract 128 bytes from remaining length to write
40E3H JC 40F4H ; Jump out of loop if less than 128 bytes remaining
40E6H JZ 40F4H ; Jump out of loop if exactly 128 bytes remaining
40E9H SHLD FCD5H ; Save updated length left to write for next pass
40ECH MVI A,80H ; Prepare to write 128 bytes to TPDD
40EEH CALL 4095H ; Send TPDD Write File opcode using RX buffer with length in A
40F1H JMP 40D1H ; Jump to send next packet of 128 bytes
; =========================================================================================
; Write remaining bytes (128 or less from above) to TPDD
; =========================================================================================
40F4H POP H ; Clear stack of unneeded updated source address
40F5H LDA FCD5H ; Load A with remainder of bytes to be sent
40F8H CALL 4095H ; Send TPDD Write File opcode using RX buffer with length in A
40FBH LXI H,0002H ; Load TPDD_CLOSE opcode in HL
40FEH JMP 409BH ; Send Request in HL and await response
; =========================================================================================
; Test if enough space on disk for HL bytes and issue Open request, error if disk full
; =========================================================================================
4101H LXI D,0500H ; Load decimal 1280 to calculate sector number
4104H XCHG ; Swap HL/DE to perform size/bytes_per_sector
4105H CALL 4C1BH ; Signed integer divide (FAC1=DE/HL)
4108H LDA FD1FH ; Get number of free sectors on disk
410BH SUB L ; Compare required sectors with free space to see if enough room
410CH JC 4881H ; Disk Full Error
410FH JZ 4881H ; Disk Full Error
4112H LDA FCD6H ; Load open mode (new, append, etc.)
4115H STA FCE8H ; Save file open mode to TX buffer
4118H LXI H,0101H ; Load TPDD_OPEN opcode
411BH JMP 409BH ; Send Request in HL and await response
; =========================================================================================
; Insert BC spaces at address of RAM file being loaded/run
; =========================================================================================
411EH LHLD FCE2H ; Load address of file being processed
4121H CALL 4C0BH ; Insert BC spaces at M
4124H JC 488AH ; RAM full error
; =========================================================================================
; Open TPDD file and read data to file address being processed
; =========================================================================================
4127H LHLD FCE2H ; Get address of file being processed
412AH PUSH H ; Save address on stack
412BH CALL 408AH ; Open TPDD file for Read Mode
412EH CALL 40B6H ; Send TPDD_READ data opcode and recieve response
4131H MOV C,A ; Move read length to C
4132H MVI B,00H ; Clear MSB of copy length
4134H POP D ; Restore address to write data
; =========================================================================================
; Write BC bytes from M to DE and subtract BC from total file size
; =========================================================================================
4135H CALL 4A05H ; Move BC bytes from M to (DE) with increment
4138H PUSH D ; Save updated address to stack
4139H LDA FD03H ; Get length byte from RX buffer
413CH LHLD FCDDH ; Get total file size from storage
413FH MOV C,A ; Load count of bytes transfered this block
4140H MVI B,00H ; Clear MSB of count
4142H DSUB ; Subtract this block from total file length
4143H SHLD FCDDH ; Save remaining bytes to be read back to temp storage
4146H JC 414EH ; Branch if too many bytes read
4149H MOV A,L ; Load LSB to A to test for zero
414AH ORA H ; OR MSB to test for zero
414BH JNZ 412EH ; Branch to read more data if not zero
414EH POP D ; Pop address from stack - cleanup
414FH RET
; =========================================================================================
; Write data to FDC Emulation mode physical/logical sector
; =========================================================================================
4150H LDA FCDDH ; Get physical sector number
4153H CPI 01H ; Test if physical sector is #1
4155H RZ ; Return if trying to write to sector 1 - reserved!!!
4156H CALL 4998H ; Flush RX queue and discard
4159H MVI A,57H ; Load FDC opcode for "W"rite sector
415BH STA FCD3H ; Save the FDC emulation mode opcode
415EH CALL 42CEH ; Send FDC emulation mode opcode
4161H CALL 4998H ; Flush RX queue and discard
4164H CALL 4176H ; Increment to next logical/physical sector
4167H LHLD FCE4H ; FDC Emulation data pointer address
416AH CALL 48D9H ; Send BC bytes to RS-232 from (HL) using XON/XOFF
416DH SHLD FCE4H ; LCD Buffer address of current file selection
4170H CALL 42EEH ; Read FDC Emulation mode response
4173H JMP 4150H ; Jump to write next sector ???
; =========================================================================================
; Increment to next logical/physical sector
; =========================================================================================
4176H LDA FD09H ; Get byte 7 from the RX buffer (logical sector length)
4179H CALL 4191H ; Get FDC Emulation RAM buffer sector length based on response
417CH CPI 35H ; Test if RAM Buffer logical sector length is "500" (1280)
417EH JZ 4189H ; Just update physical sector if RAM length = physical sector len
4181H LXI H,FCDEH ; Load pointer to logical sector value
4184H INR M ; Increment to next logical sector
4185H MOV A,M ; Get the next logical sector value
4186H CPI 14H ; Test if logical sector = 20 (There are 20 64-byte logical sectors)
4188H RNZ ; Return if not paat end of physical sector
4189H LXI H,FCDDH ; Point to physical sector storage
418CH INR M ; Increment to next physical sector - we "rolled over"
418DH INX H ; Point to logical sector
418EH MVI M,01H ; Start with logical sector #1 in new physical sector
4190H RET
; =========================================================================================
; Get FDC Emulation RAM buffer sector length based on response code in A
; =========================================================================================
4191H LXI B,0500H ; Initialize to 1280 byte sector length
4194H CPI 35H ; Compare response to test for "500"
4196H RZ ; Return if match
4197H LXI B,0040H ; Sector lenth not 1280, must be 64 bytes
419AH RET
; =========================================================================================
; Send TPDD opcode 0x08 - Go to FDC emulation mode
; =========================================================================================
419BH LXI H,0008H ; Prepare to send Opcode 0x08 (FDC Emulation Mode)
419EH CALL 4822H ; Send TPDD Command/Len in HL
41A1H CALL 49D3H ; Send 0x0D to RS-232 and Delay 3ms
41A4H JMP 4998H ; Flush RX queue and discard
; =========================================================================================
; Rename the TPDD file whose name is in "current BASIC program"
; =========================================================================================
41A7H LXI H,FC93H ; Filename of current BASIC program
41AAH LXI D,FCE8H ; Point to data area in TX buffer
41ADH LXI B,0006H ; Move 6 bytes of filename data
; =========================================================================================
; Rename the TPDD file whose name is in (HL)
; =========================================================================================
41B0H CALL 4A05H ; Move BC bytes from M to (DE) with increment
41B3H LDA FCCBH ; NADSBox / Desklink / TPDD2 flag
41B6H ANA A ; Test for TPDD server
41B7H JNZ 4258H ; Send TPDD_RENAME opcode and check response
; =========================================================================================
; Rename on a TPDD. I'm guessing the drive will allow changing a name to something
; that already exists, or there is no "rename", so TS-DOS is reading sector 1 and doing
; the rename opertaion manually, then writing sector 1 back to the disk.
; =========================================================================================
41BAH CALL 4A72H ; Send Dir Reference opcode
41BDH JNZ 487EH ; File Exists Error
41C0H LXI D,0500H ; Prepare to test for 1280 bytes of free ram (1 sector)
41C3H CALL 4308H ; Test if at least DE bytes of RAM free
41C6H LXI H,0100H ; Load HL with physical sector 1, logical sector 0
41C9H SHLD FCDDH ; Save in FDC Emulation sector storage
41CCH CALL 419BH ; Send opcode 0x08 - go to FDC emulation mode
41CFH CALL 427EH ; Load Physical sector 1 to (HL) (HL=Unused memory pointer)
41D2H LHLD FBB6H ; Get pointer to data - Unused memory pointer
41D5H PUSH H ; Push data pointer to the stack
41D6H MVI B,28H ; Prepare to test up to 40 filenames (max for TPDD)
41D8H LXI D,FC9CH ; Filename of last program loaded from tape
41DBH CALL 4269H ; Compare "Last program loaded" filename with all files on TPDD
41DEH JC 487BH ; Printer not ready / FF error
41E1H MOV A,B ; Get index in TPDD Sector 1 of filename that matches the old filename
41E2H ANA A ; Test if old filename exists
41E3H JZ 487BH ; Jump to error if filename not found in sector 1 - FF error
41E6H PUSH H ; Save address within Sector 1 of matching filename to stack
41E7H LXI D,FCE8H ; Point to TX buffer data area (payload)
41EAH XCHG ; HL <--> DE Prepare to copy new filename to Sector 1 data
41EBH LXI B,0009H ; Prepare to copy 9 bytes of filename
41EEH CALL 4A05H ; Move BC bytes from M to (DE) with increment - copy new filename to sector 1
41F1H POP H ; Restore pointer to filename address within sector 1
41F2H PUSH H ; Save it to the stack again
41F3H LXI D,FD20H ; Load address of data byte 28 in RX buffer
41F6H LXI B,001FH ; Prepare to copy 31 bytes to RX buffer from Sector 1 data
41F9H CALL 4A05H ; Move BC bytes from M to (DE) with increment - Save File data in RX buffer
; ==========================================================================================
; Now we will "remove" the renamed file from sector 1 by copying over it with the remaining
; files in the sector. Filenames in sector 1 must be in alphabetical order, so we have to
; remove it and reinsert it at the new location based on the new name.
; ==========================================================================================
41FCH POP D ; Restore pointer to filename address within sector 1
41FDH PUSH D ; Save it to the stack again
41FEH LXI H,001FH ; Prepare to add 31 bytes to the sector 1 pointer (go to next file)
4201H DAD D ; Point to next file after rename file within sector 1
4202H PUSH H ; Save address of next file after rename file to stack
4203H LHLD FBB6H ; Unused memory pointer
4206H LXI B,0500H ; Load size of 1 TPDD sector (1280 bytes)
4209H DAD B ; Point to end of sector 1 data in free memory region
420AH POP B ; Restore address of next file after rename file from stack
420BH PUSH B ; Save it back to the stack
420CH DSUB ; Calculate number of bytes from next file after rename to end of sector 1
420DH XTHL ; HL <--> (SP) Prepare to move HL to BC, HL now has address of next file
420EH POP B ; Get byte count to end of sector 1
420FH CALL 4A05H ; Move BC bytes from M to (DE) with increment - shift bytes "left" in buffer
4212H LHLD FBB6H ; Unused memory pointer - point to beginning of Sector 1 data
4215H MVI B,27H ; Prepare to search throuh 39 files (we just deleted one)
4217H LXI D,FD20H ; Load address of data byte 28 in RX buffer (our saved file)
421AH CALL 4269H ; Search Sector-1 files at (HL) for filename at (DE)
421DH PUSH H ; Save address of location where file should be inserted in Sector 1
421EH LHLD FBB6H ; Unused memory pointer - point to beginning of Sector 1
4221H LXI B,04FFH ; Prepare to move bytes "right" to end of sector (1280 bytes - 1)
4224H DAD B ; Point to end of sector 1 data
4225H PUSH H ; Save end of sector 1 address to stack
4226H LXI B,001FH ; Prepare to subtract 1 file entry length from end of sector 1 address
4229H DSUB ; Shorten the copy operation by 1 file entry so we don't overflow memory
422AH POP D ; Get end of sector 1 address from stack as our "copy to" address
422BH POP B ; Get address where file needs to be inserted from the stack
422CH PUSH B ; Save it back to the stack for later
422DH PUSH H ; Save address of end of Sector 1 minus one file entry length to stack
422EH DSUB ; Calculate the copy lenght of data from insertion point to end of sector-1 file
422FH PUSH H ; Save copy length to the stack to copy it to BC
4230H POP B ; Get copy length into BC
4231H INX B ; Increment length by 1 so the last byte is inclusive
4232H POP H ; Get address of file insertion point from stack
4233H CALL 4C4EH ; Move BC bytes from M to (DE) with decrement - shift files "right" in sector 1
4236H LXI H,FD20H ; Get address of our saved file info in the RX buffer
4239H POP D ; Get address in Sector 1 of file insertion point
423AH LXI B,001FH ; Prepare to copy 1 file entry size (31 bytes)
423DH CALL 4A05H ; Move BC bytes from M to (DE) with increment
; ===============================================================================
; Seems like the next two lines don't do anything. The value being loaded in HL
; *appears* to mean "Logical sector 20, physical sector 1", but only if the SHLD
; target address is FCCDH. Then 5 instructions further down, the value in
; ED80h is overwritten with logical sector 0.
; ===============================================================================
4240H LXI H,1401H ; Set L = logical sector 1, H=File type 0x14?
4243H SHLD FCDEH ; Save logical sector & filetype
4246H POP H ; POP stale address within Sector 1 of matching filename from stack
4247H POP H ; Get address of unused memory (Sector 1 data storage) from stack
4248H SHLD FCE4H ; Save in FDC Emulation data pointer address
424BH LXI H,0100H ; Load HL= logical sector 1, physical sector 0
424EH SHLD FCDDH ; Save in FDC Emulation physical/logical sector storage
4251H CALL 4150H ; Write data to FDC Emulation mode physical/logical sector
4254H CALL 49CDH ; Send "M1",0x0D to RS-232 and delay about 3ms - go to Standard mode
4257H RET
; =========================================================================================
; Send TPDD_RENAME opcode and check response for errors
; =========================================================================================
4258H LXI H,190DH ; Load TPDD_RENAME opcode
425BH CALL 4822H ; Send TPDD Command/Len in HL
425EH CALL 47CCH ; Receive a packet
4261H LDA FD04H ; Get response error code
4264H ANA A ; Check for errors
4265H JNZ 487EH ; Report File Exists Error if not zero
4268H RET
; =========================================================================================
; Search Sector-1 files at (HL) for filename at (DE), maximum of "B" entries searched
; =========================================================================================
4269H MVI C,09H ; Prepare to compare 9 bytes
426BH CALL 4A1CH ; Compare (HL) with (DE), C bytes long (HL & DE preserved)
426EH RZ ; Return if they are the same
426FH RC ; Return if filename is less (files are sorted on TPDD)
4270H MOV A,M ; Get 1st byte of filename to test for NULL
4271H ORA A ; Test if A is 0
4272H RZ ; Return if string is NULL
4273H PUSH B ; Save BC on stack
4274H LXI B,001FH ; Prepare to add 31 to HL
4277H DAD B ; Add 31 to HL
4278H POP B ; Restore original BC
4279H DCR B ; Decrement loop counter
427AH RZ ; Return if no more items to compare
427BH JMP 4269H ; Jump to compare next entry
; =========================================================================================
; Read FDC sectors to New File Address (Free memory)
; =========================================================================================
427EH LHLD FCE2H ; Get pointer for TPDD read data
4281H CALL 4298H ; Read sector A into (HL)
4284H LDA FCDDH ; Load current FDC Emulation physical sector number
4287H DCR A ; Decrement to previous sector
4288H RZ ; Return if sector number is zero
4289H JMP 4281H ; Jump to read another sector (what breaks the loop? - A not saved)
; =========================================================================================
; Receive RX bytes to (HL) routine copied to RAM
; =========================================================================================
428CH CALL 6D7EH ; Get a character from RS232 receive queue
428FH MOV M,A ; Save next byte to (HL)
4290H INX H ; Increment pointer
4291H DCX B ; Decrement counter
4292H MOV A,C ; Prepare to test or zero
4293H ORA B ; OR in MSB of coutner
4294H JNZ FD89H ; Jump back to receive next character (RAM address)
4297H RET
; =========================================================================================
; Read FDC sector A to (HL), BC has length
; =========================================================================================
4298H PUSH H ; Save target address for RX data stack
4299H MVI A,52H ; Load FDC Emulation opcode for "R"ead
429BH STA FCD3H ; Save as FDC Emulation opcode to send
429EH CALL 42CEH ; Send FDC emulation mode opcode
42A1H CALL 4176H ; Increment to next logical/physical sector
42A4H CALL 4862H ; Test if DSR is set - drive ready, error otherwise
42A7H PUSH B ; Save length of RX to the stack
42A8H LXI H,428CH ; Load address of RX routine to copy to RAM
42ABH LXI B,000CH ; Size of the RX routine to be copied to RAM
42AEH LXI D,FD89H ; Target address of RX routine (in ALTLCD buffer)
42B1H CALL 4A05H ; Move BC bytes from M to (DE) with increment
42B4H MVI A,0DH ; Prepare to send CR to RS-232
42B6H CALL 485FH ; Send A to RS-232 using XON/XOFF
42B9H CALL 4BDBH ; Call Main ROM's Set interrupt to 1DH routine.
42BCH POP B ; Restore count of bytes to receive
42BDH POP H ; Restore target address for RX data
42BEH RST 1 ; Call main ROM at address in following 2 bytes
42BFH DW FD89H ; Switch to Main ROM and call our RAM based RX routine
42C1H RET
; =========================================================================================
; Convert decimal value in A to base 10 ASCII value in BC
; =========================================================================================
42C2H MVI B,2FH ; Start with '0' - 1
42C4H SUI 0AH ; Subtract 10 from A
42C6H INR B ; Increment B (10's position)
42C7H JNC 42C4H ; Keep looping until A negative
42CAH ADI 3AH ; Convert negative remainder to positive ASCII '0'-'9'
42CCH MOV C,A ; Store LSB ASCII value in C
42CDH RET
; =========================================================================================
; Send FDC emulation mode opcode
; =========================================================================================
42CEH LDA FCDDH ; Get physical sector number
42D1H CALL 42C2H ; Convert A to 10-based ASCII
42D4H LDA FCD3H ; Load the FDC emulation mode opcode to send
42D7H CALL 485FH ; Send A to RS-232 using XON/XOFF
42DAH CALL 49DBH ; Send BC to RS-232 using XON/XOFF - send physical sector #
42DDH LDA FCDEH ; Get logical sector number
42E0H CALL 42C2H ; Convert A to 10-based ASCII
42E3H MVI A,2CH ; Load code for ','
42E5H CALL 485FH ; Send A to RS-232 using XON/XOFF
42E8H CALL 49DBH ; Send BC to RS-232 using XON/XOFF - send logical sector #
42EBH CALL 49D3H ; Send 0x0D to RS-232 and Delay 3ms
; =========================================================================================
; Read FDC Emulation mode response
; =========================================================================================
42EEH LXI H,FD04H ; Point to RX buffer data area
42F1H PUSH H ; Save RX buffer address on stack
42F2H MVI C,08H ; Prepare to read 8 bytes from RX - standard FDC response length
42F4H CALL 47E5H ; Get next byte from RX into HL
42F7H DCR C ; Decrement loop counter
42F8H JNZ 42F4H ; Keep looping until 8 bytes read
42FBH POP H ; Get start of RX buffer address from stack
42FCH MOV A,M ; Get first response byte
42FDH CPI 30H ; Test if response error code is '0' - no error
42FFH RZ ; Return if no error
4300H CPI 42H ; Test for FDC Emulation mode "write protect" error code
4302H JZ 486DH ; Write Protect Error
4305H JMP 4867H ; Drive Not Ready Error
; =========================================================================================
; Test if at least DE bytes of RAM left
; =========================================================================================
4308H LHLD FBB6H ; Unused memory pointer
430BH PUSH H ; Push unused memory location on stack
430CH SHLD FCE2H ; Save unused memory location locally
430FH LXI H,FFC0H ; Prepare to subtract 64 from stack pointer
4312H DAD SP ; Add SP to HL (-64) (need some call space to run program)
4313H POP B ; Restore unused memory location in BC
4314H DSUB ; Subtract stack from unused memory pointer
4315H RST 3 ; Compare DE and HL - check if enough free RAM
4316H JC 488AH ; RAM full error
4319H RET
; =========================================================================================
; Issue TPDD Delete file Opcode
; =========================================================================================
431AH XRA A ; Prepare to indicate we can't use Next Dir feature
431BH STA FD01H ; Save in dir reference location in TX buffer
431EH LXI H,0005H ; Load Delete File opcode into HL
4321H JMP 409BH ; Send Request in HL and await response
; =========================================================================================
; RST 7,2Eh Hook - DSKI$ function
; =========================================================================================
4324H POP PSW ; Pop return address - we will return manually to Main ROM
4325H CPI 30H ; Test A against '0' to check for bounds (only allow '0' and '1')
4327H JC 00A6H ; Return to Main ROM if less than '0' - not our's
432AH CPI 32H ; Test A against '2' to check for bounds
432CH JNC 00A6H ; Return to Main ROM if >= '2'
432FH SUI 30H ; Convert ASCII bank number to binary
4331H STA FCCAH ; Save the target bank number in TPDD2 Bank number space
4334H INX H ; Point to next byte to ensure it is ':'
4335H DCR E ; ? Maybe length
4336H MOV A,M ; Get next byte of filename
4337H CPI 3AH ; Test if it is ':'
4339H JNZ 00A6H ; Return if not ':'
433CH INX H ; Increment to filename portion
433DH DCR E ; ? Maybe length
433EH XTHL ; Put pointer to filename on stack so we don't lose it when we pop
433FH POP H ; Pop so we return to our caller's return address
4340H MVI A,09H ; Load A with a value we will test for later to see if it's our file
4342H ORA A ; Set return flags
4343H JMP 00A6H ; Return to Main ROM
; =========================================================================================
; RST 7,52h Hook - LFILES function
; =========================================================================================
4346H POP PSW ; POP return address from stack...we will return manually
4347H PUSH D ; Preserve DE on STACK
4348H PUSH H ; Preserve HL on STACK
4349H PUSH PSW ; Preserve A on STACK
434AH XRA A ; Flag to generate system errors vs. printing
434BH CALL 4A85H ; Save OS's baud rate string to storage area
434EH LDES 02H ; DE = SP + 2
4350H LHLX ; Get value of HL pushed to stack above - LFILES argument pointer
4351H MOV A,M ; Get 1st byte of argument
4352H ANA A ; Test if arguement is zero
4353H JZ 436AH ; Jump to display files from current TPDD bank number if zero
4356H CPI 3AH ; Test if 1st byte is ':'
4358H JZ 436AH ; Jump to display files from current TPDD bank number if ':"
435BH CALL 4BCFH ; Evaluate expression at M-1 - Convert "0:" or "1:" to decimal
435EH MOV A,E ; Get result of evaluation
435FH CPI 02H ; Compare result for bounds
4361H JNC 4370H ; Jump to exit routine if not 0 or 1
4364H STA FCCAH ; Save as TPDD2 Bank number
4367H LDES 02H ; DE = SP + 2
4369H SHLX ; Save updated expression pointer to stack location prior to RST 7
436AH CALL 4704H ; Display / print all files and free space
436DH CALL 4AC4H ; Restore original baud settings
; =========================================================================================
; RST 7 Hook exit routine
; =========================================================================================
4370H POP PSW ; Get preserved A from stack
4371H POP H ; Get preserved HL from stack
4372H POP D ; Get preserved DE from stack
4373H POP B ; B isn't PUSHed in the Hook routines, POP the return address
4374H JMP 00A6 ; Return to the Main ROM
; =========================================================================================
; RST 7,58h Hook - KILL statement
; =========================================================================================
4377H POP PSW ; POP the return address - we will return manually
4378H CPI 09H ; Test if we found "0:" or "1:" in the DSKI$ function
437AH JNZ 4516H ; Generate FC error
437DH PUSH D ; Preserve DE on the stack
437EH PUSH H ; Preserve HL on the stack
437FH PUSH PSW ; Preserve A on the stack
4380H XRA A ; Flag to generate system errors vs. printing
4381H CALL 4A85H ; Save OS's baud rate string to storage area
4384H LXI H,FC93H ; Filename of current BASIC program
4387H CALL 4A57H ; Send Dir Reference for filename at (HL)
438AH JZ 487BH ; "FF" error if attribute byte is zero
438DH CALL 431AH ; Issue TPDD Delete file Opcode
4390H CALL 4AC4H ; Restore original baud settings
4393H JMP 4370H ; RST 7 Hook exit routine
; =========================================================================================
; RST 7,5Ah Hook - NAME statement
; =========================================================================================
4396H POP PSW ; POP the return address - we will return manually
4397H CPI 09H ; Test if we found "0:" or "1:" in the DSKI$ function
4399H JNZ 4516H ; Generate FC error
439CH PUSH D ; Preserve DE on the stack
439DH PUSH H ; Preserve HL on the stack
439EH PUSH PSW ; Preserve A on the stack
439FH XRA A ; Flag to generate system errors vs. printing
43A0H CALL 4A85H ; Save OS's baud rate string to storage area
43A3H LXI H,FC9CH ; Filename of last program loaded from tape
43A6H CALL 4A57H ; Send Dir Reference for filename at (HL)
43A9H JZ 487BH ; "FF" error if attribut byte is zero
43ACH LXI H,FCE8H ; Point to TX buffer data area (payload)
43AFH LXI D,FC9CH ; Filename of last program loaded from tape
43B2H LXI B,0009H ; Prepare to copy 9 bytes of filename
43B5H CALL 4A05H ; Move BC bytes from M to (DE) with increment
43B8H CALL 41A7H ; Rename the TPDD file whose name is in "current BASIC program"
43BBH CALL 4AC4H ; Restore original baud settings
43BEH JMP 4370H ; RST 7 Hook exit routine
; =========================================================================================
; RST 7,5Eh Hook - LOADM and RUNM statement
; =========================================================================================
43C1H POP PSW
43C2H CPI 09H ; Test if we found "0:" or "1:" in the DSKI$ function
43C4H JNZ 00A6H ; Return if not a TPDD file
43C7H POP B ; Pop return address from stack - we will jump manually to exit
43C8H PUSH H ; Preserve HL on the stack
43C9H LXI B,4F43H ; Load code for "CO" filename extension
43CCH CALL 44BAH ; Compare extension in current BASIC program filename with value in BC
43CFH JZ 487BH ; "FF" Printer not ready error
43D2H CALL 408AH ; Open TPDD file for Read Mode
43D5H LHLD FD1DH ; Get file size parameter from RX buffer
43D8H MOV A,L ; Swap endianness of file size
43D9H MOV L,H ; Move MSB to LSB
43DAH MOV H,A ; Move LSB to MSB
43DBH SHLD FCDDH ; Save endian modified length back to storage
43DEH CALL 40B6H ; Send TPDD_READ data opcode and recieve response, HL=RX buf upon return
43E1H CALL 4C6AH ; Copy CO header bytes (6) from (HL) to "active" CO Header storage area
43E4H PUSH H ; Push updated (+6) RX data pointer to stack
43E5H CALL 4C6EH ; Go print CO address, length and invocation address to LCD
43E8H LHLD FACEH ; Address of CO Header - get CO load address
43EBH PUSH H ; Push CO load address to stack
43ECH PUSH H ; Push another copy to the stack to preserve value during XTHL/POP
43EDH LHLD F5F4H ; RST 5.5 RAM Vector
43F0H XTHL ; HL <--> (SP) Load RST 5.5 RAM vector as return address
43F1H POP B ; BC now has RST 5.5 RAM Vector, HL= CO load address
43F2H DSUB ; Test if CO load address is less that RST 5.5 RAM address
43F3H JC 488AH ; Trying to clober RST5.5 RAM vectors - generate RAM full error
43F6H POP D ; Get CO load address saved on stack
43F7H POP H ; Get Updated (+6) RX data pointer from stack
43F8H LDA FD03H ; Load RX Length byte from RX data buffer
43FBH SUI 06H ; Subtract CO header length from packet data length
43FDH MOV C,A ; Save packet data length in BC
43FEH MVI B,00H ; Make MSB of BC zero
4400H CALL 4135H ; Write BC bytes from M to DE and subtract BC from total file size
4403H CALL 4AC4H ; Restore original baud settings
4406H LXI H,251AH ; Load new return address in Main ROM
4409H PUSH H ; Push new return address to stack
440AH JMP 00A6H ; Jump to Main ROM
; =========================================================================================
; RST 7,5Ch Hook - SAVEM statement
; =========================================================================================
440DH POP PSW ; POP the return address - we will return elsewhere
440EH CPI 09H ; Test if we found "0:" or "1:" in the DSKI$ function
4410H JNZ 00A6H ; Return if not a TPDD file
4413H CALL 4C72H ; Process SAVEM arguments for address, length and entry point
4416H LXI B,4F43H ; Load code for "CO" file extension
4419H CALL 44BAH ; Compare ext. in current BASIC program with BC, send dir ref. if match
441CH JNZ 487EH ; Jump to generate File Exists Error if found
441FH MVI A,01H ; Set open mode for new file
4421H STA FCD6H ; Save open mode to input variable
4424H LHLD FAD0H ; Length of last program loaded/saved to tape
4427H LXI B,0006H ; Prepare to add CO header size (6 bytes) to required length
442AH PUSH B ; Push CO header length to stack
442BH DAD B ; Add CO header size to required length
442CH PUSH H ; Push updated file length to stack
442DH CALL 4101H ; Test free Disk space and issue TPDD_OPEN request
4430H POP H ; Get updated file length from stack
4431H SHLD FCD5H ; Save as lenght of file being saved / loaded
4434H POP B ; Get CO header length from stack
4435H LXI H,FACEH ; Load address of "active" CO header block
4438H LXI D,FD04H ; DE points to the data area in RX buffer
443BH CALL 4A05H ; Move BC bytes from M to (DE) with increment
443EH LHLD FD04H ; DE points to the data area in RX buffer
4441H LXI B,007AH ; Prepare to write 122 bytes of data to next location in RX buffer
4444H CALL 40D8H ; Write 122 bytes from (HL) and send TPDD_WRITE to TPDD
4447H CALL 4AC4H ; Restore original baud settings
444AH LXI H,0501H ; Load return address in Main ROM - vector to BASIC ready
444DH PUSH H ; Push return address to stack
444EH JMP 00A6H ; Return to Main ROM
; =========================================================================================
; RST 7,1Ah Hook - RUN statement
; =========================================================================================
4451H POP PSW
4452H CPI 09H ; Test if we found "0:" or "1:" in the DSKI$ function
4454H JNZ 00A6H ; Return if not TPDD file
4457H POP B ; Get return address from stack
4458H POP PSW ; Get 1st byte of RUN statement argument
4459H PUSH PSW ; Put back the data we stole
445AH PUSH B ; Put back the return address
445BH JZ 00A6H ; Return if there were no arguments to the RUN statement
445EH SBB A ; Clear zero flag (C is set and A=0xFF)
445FH STA FC92H ; Save in flag to execute BASIC program (non-zero = execute)
4462H LXI B,4142H ; Load code for "BA" BASIC file extension
4465H CALL 44BAH ; Compare ext. in current BASIC program with BC, send dir ref. if match
4468H JZ 487BH ; Jump to error if not "BA" or " " - generate "FF" error
446BH LHLD FD1DH ; Get file size parameter from RX buffer
446EH MOV C,H ; Swap endianness of file size
446FH MOV B,L ; Swap LSB to MSB
4470H MOV H,B ; Copy file size parameter back to HL
4471H MOV L,C ; Copy LSB of file size to HL
4472H SHLD FCDDH ; Store length of file
4475H CALL 44ABH ; Call NEW statement, upon return HL=address of last variable assigned
4478H INX H ; Increment to free memory space
4479H SHLD FCE2H ; Save as address of file being loaded/saved/etc.
447CH LHLD FCDDH ; Get disk file length
447FH PUSH H ; Save file length on stack
4480H PUSH H ; Push file length to stack to copy to BC
4481H POP B ; Pop file length to BC
4482H CALL 411EH ; Insert BC spaces at address of RAM file being loaded/run
4485H POP D ; Get length of disk file from stack
4486H LHLD FBAEH ; Load Start of DO files pointer
4489H DAD D ; Increment Start of DO files pointer by disk file length
448AH SHLD FBAEH ; Save updated Start of DO files pointer
448DH LHLD FAD8H ; Load pointer to address used for RAM Input processing
4490H DAD D ; Increment pointer by disk file length
4491H SHLD FAD8H ; Save updated RAM Input processing pointer
4494H CALL 4AC4H ; Restore original baud settings
4497H XRA A ; Clear zero flag and A
4498H LXI H,23F5 ; Load address in Main ROM to configure and execute current BASIC programH
449BH PUSH H ; Push return address to stack
449CH JMP 00A6H ; Return to Main ROM
; =========================================================================================
; Call "BASIC NEW" helper routine. This get's copied to RAM below.
; =========================================================================================
449FH XRA A ; Prepare to switch to Main ROM
44A0H OUT E0H ; Switch to Main ROM
44A2H CALL 20FFH ; Call BASIC NEW statement
44A5H CALL FAA4H ; Switch back to OptROM
44A8H JMP 4478H ; Jump back into RST 7,1Ch Hook - RUN statement
; =========================================================================================
; Copy "BASIC NEW" helper routine to RAM and Jump to it --- Call Main ROM's NEW statement
; =========================================================================================
44ABH LXI H,449FH ; Point to helper function to copy to RAM
44AEH LXI D,FD89H ; RAM destination
44B1H LXI B,000CH ; Length of helper funciton
44B4H CALL 4A05H ; Copy helper to RAM
44B7H JMP FD89H ; Branch to helper function
; =========================================================================================
; Compare current BASIC program file extension with value in BC or " "
; =========================================================================================
44BAH PUSH PSW ; Preserve A on Stack
44BBH PUSH H ; Preserve HL on Stack
44BCH PUSH D ; Preserve DE on Stack
44BDH PUSH B ; Preserve comparison file extension on Stack
44BEH LHLD FC99H ; Load 2 extension field bytes of current BASIC program name
44C1H LXI D,2020H ; Load 2 spaces (0x20) into DE
44C4H RST 3 ; Test if filename extension in current BASIC program is " "
44C5H JZ 44D6H ; Jump if current BASIC program filename extension is " "
44C8H POP D ; Get comparison file extension from stack into DE
44C9H PUSH D ; Push file extension back to stack for storage
44CAH RST 3 ; Test if current BASIC program filename extension matches BC
44CBH JZ 44D6H ; Jump if current BASIC program filename extension matches BC
44CEH POP B ; Get BC back off stack
44CFH POP D ; Recover DE from stack
44D0H POP H ; Recover HL from stack
44D1H POP PSW ; Recover A & flags from stack
44D2H POP B ; Pop return address - File extension doesn't match so don't run
44D3H JMP 00A6H ; Return to Main ROM
; =========================================================================================
; Store expected extension (on stack) to current BASIC program and send dir reference for
; the disk file
; =========================================================================================
44D6H POP H ; Get expected file extension "BA" or "CO" from stack
44D7H SHLD FC99H ; Save to 2 extension field bytes of current BASIC program name
44DAH POP D ; Restore DE from stack
44DBH POP H ; Restore HL from stack
44DCH POP PSW ; Restore A from stack
44DDH XRA A ; Flag to generate system errors vs. printing
44DEH CALL 4A85H ; Save OS's baud rate string to storage area
44E1H LXI H,FC93H ; Filename of current BASIC program
44E4H JMP 4A57H ; Send Dir Reference for filename at (HL)
; =========================================================================================
; RST 7,16h Hook - SAVE statement
; =========================================================================================
44E7H POP PSW ; POP return address, we will return manually
44E8H CPI 09H ; Test if we found "0:" or "1:" in the DSKI$ function
44EAH JNZ 00A6H ; Return if not a TPDD file
44EDH LXI B,4142H ; Load code for "BA" basic extension
44F0H CALL 44BAH ; Compare extension in current BASIC program filename with value in BC
44F3H JNZ 487EH ; File Exists Error
44F6H CALL 4C66H ; Update line addresses for current BASIC program
44F9H LHLD F67CH ; Start of BASIC program pointer
44FCH XCHG ; HL <--> DE DE=BASIC program strt, HL=BASIC program end
44FDH RST 3 ; Compare DE and HL
44FEH JZ 450FH ; Vector to BASIC ready - print Ok if BASIC start=BASIC end
4501H PUSH D ; Save start of BASIC program to stack
4502H POP B ; POP start of BASIC program from stack
4503H DSUB ; Subtract BASIC start address from BASIC end address
4504H MVI A,01H ; Set file open mode for new file
4506H STA FCD6H ; Save open mode to pass to function
4509H CALL 40C8H ; Write HL bytes of data from (DE) to TPDD
450CH CALL 4AC4H ; Restore original baud settings
450FH LXI H,0502H ; Load address in Main ROM of Vector to BASIC ready - print Ok
4512H PUSH H ; Push new return address to stack
4513H JMP 00A6H ; Return to Main ROM
; =========================================================================================
; Return to Main ROM's Generate FC Error routine
; =========================================================================================
4516H LXI H,08DBH ; Load address of Generate FC error routine
4519H PUSH H ; Push return address to the stack
451AH JMP 00A6H ; Return to Main ROM
; =========================================================================================
; RST 7,30h Hook - OPEN/CLOSE/READ/WRITE/LINE INPUT statement
; =========================================================================================
451DH XRA A ; Clear A to set print error flag
451EH STA FCD2H ; Set flag to generate system errors vs. print
4521H POP PSW ; POP return address ... returning manually
4522H SHLD FCCEH ; Save HL in Stack pointer upon entry location
4525H PUSH D ; Preserve DE on stack
4526H PUSH H ; Preserve HL on stack
4527H PUSH PSW ; Preserve A on stack
4528H LXI D,0004H ; Offset of the file descriptor address MSB
452BH DAD D ; Point to the file descriptor address MSB
452CH MOV A,M ; Get MSB address of FD
452DH CPI 09H ; Test if we found "0:" or "1:" in the DSKI$ function
452FH JZ 4538H ; Jump to process the sub-operation code if it's a TPDD file
; =========================================================================================
; RST 7,30h Hook exit routine
; =========================================================================================
4532H POP PSW ; Restore A from stack
4533H POP H ; Restore HL from stack
4534H POP D ; Restore DE from stack
4535H JMP 00A6H ; Return to Main ROM
; =========================================================================================
; Test the RST 7,30h sub-operation code and vector to the proper handler function
; =========================================================================================
4538H POP PSW ; Retrieve A from the stack - contains sub-operation code
4539H PUSH PSW ; Restore to stack
453AH CPI 00H ; Test for OPEN sub-operation
453CH JZ 455CH
453FH CPI 02H ; Test for CLOSE sub-operation
4541H JZ 45E8H
4544H CPI 04H ; Test for PRINT # sub-operation
4546H JZ 46B0H
4549H CPI 06H ; Test for EOF sub-operation
454BH JZ 4607H
454EH CPI 08H ; Test for LINE INPUT sub-operation
4550H JNZ 4532H
4553H LDES 06H ; Get stack location upon entry (we pushed 3 times = 6 bytes) in DE
4555H LXI H,161BH ; Not an operation we care about, load address for "Special RAM IO" routine
4558H SHLX ; Replace our return address so we return to "Special RAM IO" routine instead
4559H JMP 4532H ; Jump to RST 7,32h exit routine
; =========================================================================================
; RST 7,30h OPEN sub-operation
; =========================================================================================
455CH XRA A ; Generate system errors vs. printing
455DH CALL 4A85H ; Save OS's baud rate string to storage area
4560H LXI H,FC99H ; Load address of 1st extension byte of current BASIC program filename
4563H MOV A,M ; Get 1st byte of file extension from current BASIC program
4564H CPI 20H ; Test if opening a file with no extension
4566H JZ 456EH ; Branch to proivde "DO" default extension if non provided
4569H CPI 44H ; Test if A is 'D' - opening a "DO" file
456BH JNZ 488DH ; Generate system error 0x0C - ID Error
456EH MVI M,44H ; Change 1st extension byte to 'D'
4570H INX H ; Increment to 2nd extension byte
4571H MVI M,4FH ; Change 2nd extension byte to 'O'
4573H LXI H,FC93H ; Filename of current BASIC program
4576H CALL 4A57H ; Send Dir Reference for filename at (HL)
4579H MOV C,A ; Move attribute byte to C
457AH CALL 465BH ; Calculate offset of BASIC instruction file # EOF marker
457DH MVI M,00H ; Set EOF marker to zero - not EOF
457FH POP H ; POP PSW and discard
4580H POP H ; Restore address of FD control
4581H POP D ; Restore DE
4582H PUSH D ; Save DE back to stack
4583H PUSH H ; Save FD control address back to stack
4584H MOV D,C ; Save TPDD file attribute byte to D
4585H MOV A,E ; Move open mode to A (8=Append,1=Read,2=Write)
4586H ANI 07H ; Mask all but lower 3 bits so we get 0, 1, or 2
4588H LXI H,4AE4H ; Get address of RST 7,32h open mode to TPDD Open mode mapping
458BH MOV C,A ; Save mapping mode table offset to C
458CH MVI B,00H ; Clear MSB of offset for 16-bit add
458EH DAD B ; Calculate index address into mapping table
458FH MOV A,M ; Load TPDD open mode from mapping
4590H DCR A ; Test if TPDD open mode is Write
4591H JZ 45CDH ; Jump if opening for write mode
4594H DCR A ; Test if TPDD open mode is Append
4595H JNZ 45E0H ; Jump to open TPDD for Read mode if not zero
4598H LDA FD1CH ; Load attribute byte from RX buffer
459BH ANA A ; Opening for Append, test if file already exists
459CH JNZ 45A1H ; Jump to perform open for append if file already exists
459FH INX H ; Opening for append but file doesn't exist, increment mapping to Write
45A0H INX H ; Increment again to skip "read" mapping in table
; =========================================================================================
; Open TPDD file with open mode as specified by RST 7,32h mapping table
; =========================================================================================
45A1H MOV A,M ; Reload the TPDD open mode from the mapping table
45A2H STA FCE8H ; Point to TX buffer data area (payload)
45A5H LXI H,0101H ; Load TPDD_OPEN opcode in HL
45A8H CALL 409BH ; Send Request in HL and await response
45ABH LHLD FCCEH ; Get address of FD control
45AEH LXI D,0007H ; Load offset of write buffer length within FD control
45B1H DAD D ; Point to write buffer length within FD control
45B2H XRA A ; Clear A
45B3H MOV M,A ; Set the write buffer length to zero - just opened the file
45B4H INX H ; Increment to write buffer output pointer address
45B5H MOV D,H ; Save HL to DE to update write buffer output pointer
45B6H MOV E,L ; Save LSB of HL to DE
45B7H INX H ; Increment to MSB of write buffer output pointer
45B8H INX H ; Increment to write buffer location
45B9H SHLX ; Reset write buffer output poiner to beginning of buffer
45BAH POP H ; Restore address of FD control
45BBH POP D ; Restore DE from stack
45BCH MOV A,E ; Load RST 7,32h open mode into A
45BDH CPI 08H ; Test if open mode is Append
45BFH JNZ 45C4H ; Jump to retain open mode if not append
45C2H MVI E,02H ; Change Append open mode value to "Write"
45C4H MOV M,E ; Save open status to FD control
45C5H XTHL ; HL <--> (SP) Prepare to change our return address, saving HL
45C6H LXI H,14DEH ; Load new return address in ROM "LCD and PRT file open" routine
45C9H XTHL ; Put return address back to stack, restoring HL
45CAH JMP 00A6H ; Return to the new address in LCD and PRT file open routine in Main ROM
; =========================================================================================
; RST 7,30h open file for write mode. The Attribute byte from the Dir Ref opcode is in D
; =========================================================================================
45CDH MOV A,D ; Get the File attribute byte from the Dir Reference operation
45CEH ORA A ; Test if the file exists (will be 'F' if the file exists)
45CFH JZ 45A1H ; Jump to create the file if it doesn't already exist
45D2H PUSH H ; Save HL to the stack for restoration
45D3H CALL 431AH ; Issue TPDD Delete file Opcode - Overwriting existing file
45D6H LXI H,FC93H ; Filename of current BASIC program
45D9H CALL 4A57H ; Send Dir Reference for filename at (HL) - Need new Dir Ref
45DCH POP H ; Restore HL from stack
45DDH JMP 45A1H ; Open TPDD file with open mode as specified by RST 7,32h mapping table
; =========================================================================================
; RST 7,30h open file for read mode. Ensure the file exists via the attribute byte in D
; =========================================================================================
45E0H MOV A,D ; Load the file attribute byte from the Dir Ref opcode
45E1H ORA A ; Test if attribute byte is zero
45E2H JZ 487BH ; Generate "FF" error if file doesn't exist
45E5H JMP 45A1H ; Jump to open the file
; =========================================================================================
; RST 7,30h Sub command - CLOSE FILE
; =========================================================================================
45E8H POP PSW ; Retrieve A PUSHed by RST 7,32a entry
45E9H POP H ; Retrieve HL
45EAH POP D ; Retrieve DE
45EBH PUSH H ; Save FD control pointer to stack
45ECH MOV A,M ; Get FD control status byte
45EDH MVI M,00H ; Change FD control status to "closed"
45EFH CPI 02H ; Test if status
45F1H CZ 46DDH ; Call flush output buffer routine if opened for write mode
45F4H LXI H,0002H ; Load TPDD_CLOSE opcode into HL
45F7H CALL 409BH ; Send Request in HL and await response
45FAH CALL 4AC4H ; Restore original baud settings
45FDH POP H ; Restore FD control pointer
45FEH XTHL ; HL <--> (SP) so we can preserve HL through POP
45FFH POP H ; Pop return address (actually FD control address) from stack
4600H LXI H,4D59H ; Load new reuturn address - LCD, CRT, and LPT file close routine
4603H PUSH H ; Push new return address to stack - not returning to caller
4604H JMP 00A6H ; Return to Main ROM
; =========================================================================================
; RST 7,30h Sub command - EOF
; =========================================================================================
4607H CALL 465BH ; Calculate offset of BASIC instruction file # EOF marker
460AH MOV A,M ; Get the current EOF marker
460BH MVI M,00H ; Set the EOF marker to zero to reset it
460DH ANA A ; Test if at EOF for this file
460EH JNZ 4627H ; Jump if EOF marker for this file not zero
4611H LHLD FCCEH ; Get address of FD control
4614H LXI B,0007H ; Offset of write buffer length within FD control
4617H DAD B ; Point to write buffer length
4618H MOV A,M ; Get current write buffer length
4619H INX H ; Point to LSB of read/write buffer output pointer within FD control
461AH PUSH H ; Save address of read/write buffer output pointer to stack
461BH ANA A ; Test if data left in the buffer
461CH CZ 4663H ; Call to read more data from TPDD if buffer empty
461FH POP D ; Restore address of read/write output buffer within FD control
4620H LHLX ; Get current read/write pointer location from FD control
4621H MOV A,M ; Read the next byte from the buffer
4622H INX H ; Increment buffer pointer to the next byte
4623H SHLX ; Save read/write buffer pointer back to FD control
4624H DCX D ; Decrement back to read/write buffer length within FD control
4625H XCHG ; HL <--> DE Prepare to update buffer length
4626H DCR M ; Decrement length since we just read a byte
; =========================================================================================
; Test if EOF for BASIC file #
; =========================================================================================
4627H CPI 1AH ; Test if byte is EOF marker
4629H STC ; Ensure the Carry flag is set
462AH CMC ; And now clear it to indicate not EOF
462BH JNZ 4633H ; Jump if not at end of file
462EH CALL 465BH ; Calculate offset of BASIC instruction file # EOF marker
4631H MOV M,A ; Save EOF marker for this file #
4632H STC ; Set Carry to indicate EOF
; =========================================================================================
; Save EOF status
; =========================================================================================
4633H PUSH PSW ; Save EOF indication in Carry flag and marker value to stack
4634H LDES 10H ; Load offset to our return address (we PUSHed a bunch to the stack)
4636H LHLX ; Load HL with our return address from the stack
4637H LXI B,189AH ; Load address of return within EOF function
463AH DSUB ; Test if we were called from the EOF function
463BH JNZ 464FH ; Jump if not called from ROM EOF function - don't to EOF logical testing
463EH CALL 465BH ; Calculate offset of BASIC instruction file # EOF marker
4641H POP PSW ; Retreive EOF and marker value from stack
4642H MOV M,A ; Save the marker value to the file # marker storage location
4643H MOV C,A ; Save marker value in C
4644H SBB A ; Subtract with borrow (C was set if EOF)
4645H CALL 4BCBH ; Call into SGN function to set FAC1 with sign of A (EOF test)
4648H LDES 12H ; Prepare to "POP" 6 register pairs from the stack all at once
464AH XCHG ; HL <--> DE HL now has new stack value
464BH SPHL ; HL <--> SP "POP" 6 values from the stack
464CH JMP 00A6H ; Return to Main ROM
; =========================================================================================
; Non-EOF function call return
; =========================================================================================
464FH POP PSW ; Restore PSW with EOF indication (C flag)
4650H POP H ; Pop old PSW - we don't want it
4651H POP H ; Resore HL from stack
4652H POP D ; Restore DE from stack
4653H XTHL ; Push HL to stack to set new return address
4654H LXI H,4E8AH ; Load address of a "Stack frame retrun" routine
4657H XTHL ; Stack gets new return address, restore HL
4658H JMP 00A6H ; Return to the new address (not returning to parent)
; =========================================================================================
; Calculate offset of BASIC instruction file # EOF marker
; =========================================================================================
465BH LHLD FAA2H ; Get file # of active BASIC instruction (EOF, LINE INPUT, etc.)
465EH LXI D,FA91H ; Load base address of file status array
4661H DAD D ; Add offset to base of file status byte array
4662H RET
; =========================================================================================
; RST 7,30A Read data from server (TPDD) into FD file buffer
; =========================================================================================
4663H LXI H,0003H ; Load TPDD_READ opcode in HL
4666H CALL 4822H ; Send TPDD Command/Len in HL
4669H CALL 47CCH ; Receive a packet
466CH LDA FD02H ; Get response byte from storage for RX packet
466FH CPI 10H ; Test for valid read file response
4671H JNZ 469EH ; Branch if not valid read from file response
4674H LDA FD03H ; Get length of read from RX buffer
4677H LHLD FCCEH ; Get pointer to FD control
467AH LXI D,0008H ; Offset of address of read/write buffer relative to FD control
467DH DAD D ; Point to address of read/write buffer within FD control
467EH PUSH H ; Save address of read/write buffer to stack
467FH MOV D,H ; Move address of read/write buffer to DE for update
4680H MOV E,L ; Move LSB
4681H INX H ; Increment to MSB of read/write buffer address in FD control
4682H INX H ; Increment to read/write buffer
4683H SHLX ; Reset pointer to read/write buffer - we just read more data
4684H LXI D,FD04H ; DE points to the RX data in the buffer
4687H XCHG ; HL <--> DE Prepare to move data from RX buffer to FD buffer
4688H MOV C,A ; Move the RX data length to C
4689H MVI B,00H ; Clear MSB of BC count
468BH CALL 4A05H ; Move BC bytes from M to (DE) with increment - copy to FD buffer
468EH LDA FD03H ; Get length of RX read data again
4691H CPI 80H ; Test for maximum read length
4693H JZ 469AH ; If maximum read, skip writing EOF marker to read/write buffer
4696H XCHG ; HL = destination address in FD buffer
4697H MVI M,1AH ; Terminate .DO file in FD read/write buffer with EOF marker
4699H INR A ; Increment length to reflect EOF marker
; =========================================================================================
; RST 7,32A Read - not max read size
; =========================================================================================
469AH POP H ; Get address of read/write buffer in FD control from stack
469BH DCX H ; Decrement to FD control read/write buffer length location
469CH MOV M,A ; Save length of data in read/write buffer to FD control
469DH RET
; =========================================================================================
; RST 7,32A Read - unsuccessful TPDD read
; =========================================================================================
469EH LHLD FCCEH ; Get address of FD control
46A1H LXI D,0007H ; Load offset of output buffer count in FD control
46A4H DAD D ; Point to output buffer length in FD control
46A5H MVI M,01H ; Set read/write buffer length to 1 to indicate EOF marker
46A7H INX H ; Increment to LSB of read/write buffer output address in FD control
46A8H MOV D,H ; Save HL in DE for update of read/write buffer output in FD control
46A9H MOV E,L ; Save LSB of HL to DE
46AAH INX H ; Increment to MSB of read/write buffer in FD control
46ABH INX H ; Increment to the FD read/write buffer
46ACH SHLX ; Reset the FD control read/write buffer pointer to begining of buffer
46ADH MVI M,1AH ; Write an EOF marker to the buffer
46AFH RET
; =========================================================================================
; RST 7,32h PRINT # sub-operation
; =========================================================================================
46B0H LHLD FCCEH ; Pointer to FD control
46B3H LXI D,0007H ; ?Offset to output byte count
46B6H DAD D ; Get pointer to file's output byte count
46B7H MOV A,M ; Load byte count of pending bytes to write
46B8H CPI 80H ; Test if 128 bytes to write
46BAH CZ 46DDH ; Call routine to flush output buffer to file
46BDH POP PSW ; Restore A from stack (from RST 7,32h entry)
46BEH POP H ; Restore HL from stack
46BFH POP D ; Restore DE from stack
46C0H POP H ; Pop the return address - we will return via JMP
46C1H POP PSW ; Get the caller's A so we know what byte is being written
46C2H PUSH PSW ; Put it back on the stack...it isn't ours
46C3H CPI 1AH ; Test if writing an EOF marker to the file
46C5H JZ 46D6H ; Jump if writing EOF marder to the file - don't actually write it
46C8H LHLD FCCEH ; Get address of FD control
46CBH LXI D,0007H ; Get offset of output buffer length within FD control
46CEH DAD D ; Point to output buffer length address
46CFH INR M ; Increment the output buffer length - writing 1 byte
46D0H INX H ; Point to current file location pointer in FD control
46D1H XCHG ; HL <--> DE Move address of file location pointer to DE
46D2H LHLX ; Load current file location address to HL
46D3H MOV M,A ; Save the byte in the buffer (RX buffer for subsequent write)
46D4H INX H ; Increment the curent file location pointer (we will flush later)
46D5H SHLX ; Save the update current file location pointer to FD control
46D6H LXI H,14EAH ; Load address to update automatic timer and POP regs from the stack
46D9H PUSH H ; Push new return address. We will return to the parent's caller
46DAH JMP 00A6H ; Return to Main ROM
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