Date   : Mon, 18 Jul 1983 00:29:00 EDT
From   : Keith Petersen <W8SDZ@mit-mc>
Subject: MDM711.FIX

The following is forwarded from my RCPM system.  Irv Hoff
(the author of MDM711) has seen this and approves.  Because
this is a simple fix, there will be no update to MDM711 but
it will be incorporated in the next version if/when it comes
out.  There are no plans for a new version at this time.
--keith

--forwarded file: MDM711.FIX--

MDM711.FIX                July 14, 1983

There is a problem with MDM711,  in that when you are transfering 
files  in  the ASCII mode the CTRL 'Y' character that is used  to 
toggle  open  the  memory buffer is not  trapped  by  the  MDM711 
program.   By not trapping the character it is sent to the system 
you  are downloading from.   In the case of many mainframe systems 
the Ctrl 'Y' character is decoded as an EOF and the command  that 
you  were  using to transmitt the ASCII text will  be  terminated 
before you are able to capture any of the text.
 
There is a simple fix which can be made by using DDT or a similar 
type  program  to  modify the MDM711XX.COM file  you  are  using.  
This  fix does not alter the code but it does vector the  program 
off  to a MORE correct location than it is now.   All the tests I 
have performed so far seems to indicate that the change does  not 
cause  any furthur problems except for the fact that now only the 
Ctrl 'Y' is trapped, but the Ctrl 'R' (used to close your capture 
buffer) is still passed to the transmitting system.   As fas as I 
know the Ctrl 'R' will not cause any problems if it does you will 
need to modify the MDM711.ASM file at NOLST1: (123C H) TO NOLST3: 
(125D H) so that it works correctly.  

I  was reluctant to make changes to the MDM711.ASM file since  it 
was so new,  and this simple single byte 'FIX' seems to take care 
of the problem.
 
STEP 1 :     A>DDT  MDM711XX.COM
               DDT VERS 2.2
               NEXT  PC
               4300 0100
STEP 2:        -S125C            Type in S125C and then CR
STEP 3:        125C  10  44      Type in 44 and then CR
STEP 4:        125D  19  .       Type in . and then CR
STEP 5:        -G0               Type in G0 to exit DDT

STEP 6:        A>SAVE 66 MDM711XX.COM  (File now modified)


Thats  all you need to do to the program.   You can do it to  the 
MDM711XX.COM  file you are using or to the MASTER MDM711.COM file 
that  is  in the MDM711.LBR file.   If you do it  to  the  MASTER 
MDM711.COM file then it will propogate to other configurations of 
the MDM711 program with the proper overlay file.

Dennis Recla   
Dallas, Texas   Data 214 681-4789  300 baud 

With Ample assistance of Lee Wilkerson