Tony Firshman wrote:
>This is all done after 1am, just having returned from Eindhoven, so
>would welcome correction (even by myself when I re-awake later)
>
>DSR/DTR connections are not needed.
>
>QL ser1 is identical to ser2 other than RX/TX and CTS/DTR(RTS)
swapped.


=====================================================================
QL           QL              QL CABLE  QL         PC         PC    PC
ser1         ser2            COLOUR   SIGNAL     SIGNAL      25D   9D

(modem?)     (terminal?)
=====================================================================
3 (RxD o/p)  2 (TxD o/p)  <-  white    TxD        RxD    <-  3 RxD 2
2 (TxD i/p)  3 (RxD i/p)  ->  green    RxD        TxD    ->  2 TxD 3
5 (CTS)      4 (DTR=RTS)  ->  blue     DTR(=RTS)  CTS    ->  5 CTS 8
4 (DTR=RTS)  5 (CTS)      <-  red      CTS        RTS    <-  4 RTS 7
1            1            --  black    GND        GND    --  7 GND 5
N/A          N/A                                             6 DSR 6
N/A          N/A                                            20 DTR 4
=====================================================================

NOTES:
1) QL SER1 is wired as DCE, Data Communications Equipment. Essentially
as a modem.
2) QL SER2 is wired as DTE, Data Terminal Equipment. Essentially as a
computer.

>I think this way of laying it out says it all.

Ouch, my brain hurts now, this makes even less sense than it did
before. Everything seems back to front somehow. Or is it just the
different QL labelling/interpretation of each signal which confuses
me?


Reading the QL manual, the way SER1 is wired, it is in essence a modem
in terms of wiring, while SER2 is in essence a terminal or computer,
so SER2 is perhaps the easiest to visualise in this context for
computer to computer connection.

Did you perchance get PC CTS and RTS pin labelling the wrong way
round? If you did, it starts to make sense. QL SER2 is in essence
wired as a computer or terminal RS232 according to the manual, in
which case we end up with a lead which is RxD-TxD, TxD-RxD,
DTR=RTS-CTS, CTS-RTS which is what I end up with in the slightly
amended (i.e. PC RTS and CTS labelling swapped as per the note I
pulled off the internet). The pin numbers you gave look to be what I
would expect, but the labelling didn't!

The diagram above is now how I think it should look. Can someone have
another look at it to see if it's now correct!

--
Dilwyn Jones
[EMAIL PROTECTED]
http://www.soft.net.uk/dj/index.html

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