Amiga.org
Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: jjans on October 12, 2003, 03:48:15 AM
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I wish to connect 2 A500's via parallel cable and parnet.device.
I think the documentation for the installation is pretty straight forward. I am not so 100 % on the doc for modyifying the cable however.
I purchased a parallel cable for connecting 2 PC's together.
It says to connect wires 10 &13. It also says that wires 17 to 25 need to be 'bused' together.
Has anyone done this mod?
What exactly does 'bused' mean?
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I've never used a Parnet connection, but referring to:
ParNet Parallel (http://www.hardwarebook.net/cable/parallel/parnet.html) at The Hardware Book, it looks like 17-25 share a common connection- i.e. the Signal Ground! But The Hardware Book's diagram looks different to the description in the ParNet archive!!!! Remember that PC and Amiga PARELLEL Ports have differences!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!1
Here's an Aminet page on ParNet related downloads:
aminet string=Parnet (http://us.aminet.net/aminet/aminet.cgi?string=Parnet)
Connecting the two PARALLEL Ports of Amigas togather:-
CABLE: Connect D7-D0,SEL,,POUT, and BUSY across,
Connect ACK, (FLAG interrupt) to SEL locally:
(2-9) D7-D0 ------------- D7-D0
(12) POUT ------------- POUT
(11) BUSY ------------- BUSY PARALLEL PORT
(13) SEL --+-------+-- SEL
(10) ACK -/ \- ACK
(18-22) GND ------------- GND (18-22)
(( Diagram WARNING -- COPY that to a Text Editor, and space
the 'numbers', 'TITLES' & 'Lines' into columns! There is NO
connection ACK-to-ACK but those are BRIDGED to each SEL ))
(( i.e.: SPACE those '/''\' chars apart!!! ))
° Cut-and-seal those wires not supposed to be connected!
° ACK and SEL to be bridged as per diagram!
There is a further WARNING concerning the SERIAL Port:
The RI (Ring Indicate) line on the Amiga's serial port
uses the SEL line to source a transitor, which can inter-
fer with the SEL line which is part of the network.
(a) either no serial cable is attached, or
(b) it doesn't connect RI, or
(c) your modem doesn't connect RI internally!
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I have made it once, but it's way back. It worked fine though; I have hooked an A500 with an A1200, an A500 with an A600, and no problems there.
If I recall correctly the only thing I did was to connect wires 10 and 13, but I'm not sure. The only thing I'm sure of is that it only took me 5 min. You can probably find a guide that takes you through the whole creation of the cable on Aminet. Send me an mail if I should dig out my old papers.
And then a little comment. I have been told that the cable mustn't exceed 5 metres. If it does files isn't transfered correcly, and therefore it gives corrupted files. I don't know if the info is correct, so if anyone can verify that I would be grateful. My cable is 5 metres though and no problems there.
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The distance limitation is because in a parallel data cable, seperate bits of data travel down different wires in the cable at the same time.
The trouble is that due to natural variation, data travels down some of these wires a little faster than others. Over a short distance, this doesn't matter, but over a long distance it's enough to cause "data-skew", where the data doesn't arrive at the same time, and this causes corruption.
It stands to reason, however, that your parnet cable can be as long as any printer lead. The longest printer cable I've seen was probably about 5 metres. (Edit: I've just seen a 10m cable for sale online. Couldn't find anything longer than that.)