Re: null modem connection IIC / PC troubleshooting!

[Rubywand <rubywand@swbell.net>]

Deacon Blue writes ...
> 
> I have built a new cable DIN-5M  ---> DB9F consisting of only three wires:
> 'TX', 'RX' and 'ground' connected.  The pins used on DB9F is  #2,  #3 and
> #5.
> 
> ---->Win98:
> When using the 'Hyperterminal' from Win98 I manage to do ASCII-text file
> transfers to the IIC at baud rate 300 with 200 ms delay on each text-line.
> In this way I've managed to upload the ADT-source to the IIc.
> 
     So far, so good. Did you check your transfer of ADT? If you did not and
would like to, see the info below. Otherwise hop over the following snip.


>>

     In case ADT does not seem to be working correctly, you
may want to check that the transferred program was not 
corrupted. ADTCK is a short program you can type in and run
to check that you have a good copy of ADT on your Apple II.


     The check is valid only if you have not changed any of
the defaults. (Changing one or more default settings changes
the settings you see when you first start the program. The 
program is changed and saved with the new settings.)

     If you are fairly certain that you have not changed
any of the defaults, skip ahead to the program listing.
Otherwise, boot the DOS 3.3 disk which has ADT and, at the 
usual Applesoft prompt, 

BLOAD ADT

     Do a 

CALL -151

to get into the monitor (you should get the "*" prompt).

     In the monitor enter 

803.80D

     If your ADT defaults are the originals, you should see ...

0806- 05 00
0808- 01 05 01 00 00 00

If your values are different, you can change them back by entering:

806:05 00 01 05 01 00 00 00

Do a Cntrl-Reset to get back to Applesoft. Save ADT

BSAVE ADT,A$803,L$A14



     Type in the program below and save it as ADTCK on the same
disk as ADT. Then, RUN ADTCK and check the numbers you get
against the checksums listed after the program. (The program
displays intermediate sums and a final sum.)


 10  TEXT : HOME
 20  PRINT  CHR$ (4)"BLOAD ADT,A$4000"
 40  FOR I = 0 TO 2579
 50 Z = Z +  PEEK (16384 + I)
 55  IF I / 500 =  INT (I / 500) THEN  PRINT "CURRENT SUM= ";Z
 60  NEXT I
 70  PRINT "CHECKSUM= ";Z



     To check your copy of ADT v1.22

RUN ADTCK

The program displays intermediate sums and a final sum. Check
the numbers you get against the checksums listed below: 

Checksums

ADT v1.22

76     
53958 
101079
158919 
224504
307117
312869  <-- final sum

<<




> ----> DOS-operation:
> I followed your advice on using a true DOS-environment and tried to
> reproduce the same ASCII transfer from  MSDOS 6.22 by issuing the commands
> acc. to Rubywand FAQ:
> 
> >mode com1: 300,n,8,1
> >type  adt.dump > com1
> 
> But the PC resonds with message:  "Cannot write to Com1:  Retry, Ignore
> Fail?"

     The usual reason for getting this error message is that DOS thinks the
COM1 port is assigned for use by some other program. You may have left some
program (like HyperTerm) connected to COM1 in Windows. 


> (I've got a regular modem on 'com2', and issuing the samme command-set to
> this port, the modem flashes up and receives data normally)
> 
> ----> ADT-operation:
> I've tried to run the ADT 1.22 package, but cannot get any response from the
> PC-side while sending "Directory,.Receive, Send".  The IIC -screen turns
> black, or reports "Awaiting response from PC".  I've tried different speeds
> 1200,9600 etc. but  with no effect.
>
 ....

     Your 3-wire cable should be okay for doing a transfer with no flow control
(like the transfer of adt.dmp).  Once ADT is running it uses hardware
handshaking to do transfers. So, it needs some signal lines missing in your
3-wire cable.

     A good looking cable design is presented on the Apple //c .dsk Archive
site at http://www.multimania.com/apple2c/tech/Transfert.htm . The numbering
shown for the //c connector appears to be DIN-5 rather than Apple's. Apple
numbers the pins for a //c male connector (looking at the plug from the front)
in sequence as follows:


 1       5
  2     4 
     3 


     The Apple //c .dsk Archive site seems to be using this numbering:

 1       3
  4     5
     2




Rubywand