Msg: 513 *Conference*

09-15-91 21:23:55

From: JAMES FIELDS

To : TRACY ALLEN

Subj: CAPTURING RS232

TRACY,
    What I want to do is to capture the incoming RS232 signals to replace the
keyboard but still be able to use the INPUT Statement.
   EXAMPLE:
        driver active
        INPUT A$
        Any characters coming in on the serial lines are put in to the keyboard
buffer (ignore keyboard input)
        driver inactive
        INPUT A$
        Any characters typed in on the keyboard are put in to the key board
buffer (ignore RS232 input)
  
At this time, I am writting an Assemlby program to do something like this.  It
looks like I may be able to use it both as INPUT and PRINT (having problems at
the moment with variable assignment-- the machine code in ROM returns to BASIC
when it has a TM error).  The format for the call will be: CALL
address,switches,parameter address
   Swithes: the passed value for the A register tells text/no text, text
only/get input, and others to be added later (PRINT and/or INPUT)
   Parameters: string that has text (ends with ;) and/or input variables
    "[text;][var1[,var2[,ect.]]"
   The parameter list ends with a null  NOTE: the PRINT function will stop at a
; or null (chr$(0)). So far, the print function and input to computer work
fine: variable assignment is another thing.  For you and any one else that
reads this: If anyone has written a machine language LET function that returns
an error code or set flags instead of reporting a TM error to BASIC, please
leave a source copy for me (the assignment must be able to assign to BASIC
variable names such as AB, Q$, R!, ect)
                JAMES FIELDS