Subject : IMP overlay customization
From : Irv Hoff
Date : 17 July 85
The following notes will help the IMP user to select various
user options. The ones that should be quite self-explanatory will not
be included in the list.
0103 MSPEED - use 05 for 1200, 06 for 2400.
0104 HS2400 - YES if 2400 is your top speed, otherwise NO
0105 HS1200 - YES if 1200 is your top speed, otherwise NO
0106 RACAL - YES if using a Racal-Vadic modem with autodial
(the 1200v and 2400v can also use the Hayes
AT protocol, but the Racal-Vadic protocol
displays additional progress reports.)
- NO for "AT" protocol developed by Hayes
0107 PROMODM - YES if using the Prometheus ProModem 1200, else NO
010A CLEAR - Most computers can clear the CRT with a CTL-Z, if
yours does, put a 1BH (CTL-Z) here. Some use an
"ESC-x" (the "x" may be a upper or lower case ASCII
character.) Put that character in this location, the
ESC will be automatically added if an ASCII character
is present. Put a 0 here if you don't know what your
terminal needs, it will then scroll 24 blank lines to
clear the screen.
010B CLOCK - This value is your clock speed times 10, for more
variation. A 4 MHz clock would use 40. (Convert to
hex if installing via DDT.) This just sets the time
for some of the internal delay loops. It can be
changed to whatever is needed to make those more ac-
curate.
010C BYTDLY - This puts a delay between characters when sending an
ASCII file in the terminal mode.
010D CRDLY - This puts a delay after a CRLF when sending an ASCII
file in the terminal mode. Sometimes these are used
on systems that cannot accept messages at full speed.
010F TCHPUL - Some modems (such as the Racal-Vadic, Prometheus,
etc.) can auto-sense if they can touch-tone dial or
need to pulse dial. Put a 0 here (do not use '0'
which is an ASCII value) if you want your modem to
auto-sense what it can use. Else a 'T' or 'P'.
0114 EXTCHR - This is the local control "lead-in" character when in
the terminal mode. Currently set to ESC. Some ter-
minals don't have ESC or the operator may prefer some
other character. Put it here.
The characters from 0115 through 011C are the local
control characters and may easily be changed to suit
the operator's preference - if different.
0168 J$STRNGA - This jumps to the 'AT' initialization string for
1200 bps modems.
0169 J$STRNGB - This jumps to the 'AT' initialization string for
2400 bps modems. If the user wants to develop his
own customized initialization string, just change
this to jump to your own routine.
In writing these routines, you can use J$ILPRT for
strings (terminate with a 0 character) for local
display, "CALL J$CRLF" for a new line on the CRT,
J$SNDSTR to send a string to the modem (end with $),
J$SNDCHR to send a single character to the modem, and
'#' character is a 0.1 second delay. Including ###
in the string to the modem would cause a 300 ms.
delay, etc. (250 ms. minimum needed after an 'AT'
string is completed by a CR before the modem should
be given any other duty.)
The J$ commands just listed would allow the user to
add routines to set parity, stop bits, different
initialization strings, etc.
ROOM REMAINING
--------------
There are 601 characters remaining after the start of the SYSVR
label. The routines in the overlay should stop by 0400H. In the case
of the I2DP-1 overlay, that would leave an additional 223 bytes for any
customization the user might add.
- Irv Hoff
Los Altos Hills, CA
(415) 948-2166 - voice
