SET UP ROUTINE FOR THE CP/M MODEM PROGRAM. 9/15/80
This information is given for those who do not wish to re-assemble
the modem program for their system because they do not have MAC, do
not have the source code, or are lazy. If you have a PMMI Modem board,
with base port set at E0H, and do want backup (.BAK) copies (if the file
being received already exists), the program will run as is. If not,
make the patches listed below.
Use the L command ( L100 ) of DDT or SID to list the program and
use the S command to make the following changes:
0100 C3 2D01 JMP 012DH <--- Do not change
(Note: The L command of DDT or SID displays 0FFH as "RST 07" and 0 as "NOP")
0103 FF <--- 0FFH if PMMI modem, else zero
0104 FF <--- 0FFH if Imsai with front panel,
else zero.
0105 00 <--- 0FFH if 4 MHz Z-80 (or maybe fast 8085)
else 0
0106 00 <--- Zero if you want files that exist
to be deleted if a file of the same
name is sent in multifile transfer.
0FFH if you want the existing file
to be changed to type "BAK".
Note: In CP/M 2 existing R/O or
SYS files are changed to
type BAK whether this byte
is set or not.
0107 FF <--- 0FFH if you want program to come
up in expert (XPR) mode without
calling A>MODEM X else zero if
you want menu or X command.
0108 7D <--- 7DH for 20 pulses/sec dialing
PMMI (PMMI modem only). 0FAH if your
ONLY phone exchange is older and needs
a slower dialing rate.
0109 DB XX IN XX <--- Put modem status port in 010AH
010B C9 RET (Base port if PMMI)
If you have a PMMI modem board, no other patches need be made.
Leave DDT with ^C and type
SAVE 35 MODEM.COM (OR M.COM)
If you do not have a PMMI modem, make the following patches also:
010C D3 XX OUT XX <--- Put modem data port in 010DH
010E C9 RET
010F E6 XX ANI XX <--- Put bit tested when modem ready to
0111 C9 RET send in 0110H
0112 FE XX CPI XX <--- Same as 0110H if port uses positive logic (JZ).
0114 C9 RET Hex zero if port uses negative logic (JNZ).
0115 DB XX IN XX <--- Put modem data port (again) in 0116H.
0117 C9 RET
0118 E6 XX ANI XX <--- Put bit tested when modem ready to receive
011A C9 RET in 0119H
011B FE XX CPI XX <--- Same as 0119H if port uses positive logic.
011D C9 RET Hex zero if port uses negative logic.
011E C3 XXXX JMP XXXX <--- 011EH contains a jump to a modem or port
initialization routine. If your modem does
not need to be initialized, put a RET (C9H)
in 011EH .If you need initialization, write
your routine for the memory location addressed
by the jump. The initialization routine
must end with a RET instruction. You have
approximately 190 (decimal) bytes for the
routine.
