Null Cable Modem For //C

2 replies [Last post]
A2forever's picture
Joined: Dec 20 2003
Posts: 226


can someone please tell me which null cable modem I would use to hook up a //c or //c plus to my pc? for use with apple disk transfer?




Long Live The Apple ][

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
blackbag's picture
Joined: Oct 10 2005
Posts: 31

From the CSA2 Faq:

016- I've heard that I can use some sort of printer cable to do
NULL modem transfers with between my IIc and a PC. Which cable?

Get an "Apple IIc to ImageWriter I" cable. It has a DIN-5 plug on one end
and a standard Dsub-25 plug on the other with the correct line swapping for
NULL modem. Depending upon whether your PC connection is to a 25-pin or 9-pin
port and whether or not an extension cable is used, you may also need a Dsub-25
to Dsub-9 cable and/or a Dsub-25 gender changer. (The latter are standard items
at many computer stuff stores.)

blackbag's picture
Joined: Oct 10 2005
Posts: 31
IIc plus

The IIc Plus has a different serial port type. It uses the smaller connectors like the ones on a IIgs. The normal IIc uses the lareger Din-5 connector. So, you could probably get a IIgs imagewriter 1 connector and use a gender changer/9/25 pin adapter to get it to your PC. If you want to create your own cable here what you need:

Dedicated IIgs NULL modem cable

The usual IIgs NULL modem cable consists of a High-Speed IIgs modem cable
connected to a NULL modem adapter which connects to a modem cable coming
from the PC. If you want to 'roll you own' single piece IIgs --> PC cable for NULL modem connections, here is the pinout info:

IIgs PC Female Dsub
Mini-Din 8 Dsub-25F or Dsub-9F Dsub Signal

3 3 2 RXD
5 2 3 TXD
4,8 7 5 GND
2 4 7 RTS
1 5,6,8 1,6,8 CTS, DSR, DCD
7 20 4 DTR

Also, from experience, I have found that a console cable from an SGI Indy machine works perfectly as-is for IIgs transfers -- If you happen to have one of those available to you.