Msg: 5714 *Conference*

03-21-95 14:40:07

From: RON WIESEN

To : CARSTEN MARTENSEN

Subj: REPLY TO MSG #5708 (102/MODEM)

You can use the RS-232 port with an external modem to download files at up to
1200 bits per second via TELCOM.  You must defeat the LCD scroll.  Once
defeated, incoming text simply over writes the bottom line of the LCD but the
Download (TELCOM F2) captures the text.  It's only when TELCOM must scroll the
LCD (copy lower 7 lines to upper 7 lines to scroll 1 line) that the effective
transfer rate is limited to less than 600 bits per second.
 
The typical trick is to assign TELCOMs TERMinal mode F6 or F7 hooks to a few
bytes of code that pokes the scroll disable.  Upon entry, TELCOM enables scroll
so that is why you must link some code that disables it into TELCOM.
 
In the library, under (3)TELCOM, is the TOGGLE.BA program by Paul Globman which
does the trick nicely.  TOGGLE.BA assigns TELCOMs TERMinal mode F6 as a toggle
for LCD scroll  --  each time you press F6 the scroll alternates: disabled;
enabled.  TOGGLE.BA simply puts the toggle code (about 3 instructions) in
otherwise wasted bytes of the BASIC F4 (Run) function key definition area and
then permanently sets the TELCOM TERM F6 vector to link the code.  You could
place the code in some other location, as long as it's a static location (can't
use a .CO file).  Naturally, you would not want to redefine the BASIC F4 key
without first removing the linkage from TELCOM TERM F6, otherwise cold starts
can occur.  This is explained, and a removal method is outlined, in the Paul
Globman's comments within TOGGLE.BA.
 
I use something similar of my own making where TELCOM TERM F6 is just a chord
strike that in conjunction with the CTRL, SHIFT, and GRPH keys sets Carriage
Return/Line Feed or Carriage Return-only line end treatements respectively for
the PRINTER, RS-232, and LCD.  In the case of the LCD, I'm calling Carriage
Return-only the line end treatment that disables the LCD scroll.