Apple IIgs modem cable

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Apple IIgs modem cable

I have what I believe is a null modem cable for my iigs. (It works with ADTPro) I got a modem that is 9pin. I can get this to work on my PC with a usb to 9 pin adapter. So I know the modem works.

As it is with the cable I have that is 8pin to db9 I cannot get the modem to work.

I want to build a cable that will connect to the null modem cable on the db9 side and re-wire it so it will work with the modem which is a db9 connector on it. It is a serial to wifi modem board.  

I have been searching all over the internet for a pin out diagram with no success. Does anyone know how to accomplish this or point me in the right direction?  I already have supplies to make the cable "converter". 

 

Thanks for your time reading this. 

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Looking at the IIgs serial

Looking at the IIgs serial connector, the pins are numbered as follows:

  8   7   6

  5   4   3

    2   1

The signals on each pin are:

1  Handshake Out (DTR)

2  Handshake In (DSR)

3  Transmit Data minus

4  Signal Ground

5  Receive Data minus

6  Transmit Data plus

7  General purpose input (DCD)

8  Receive Data plus

 

Shield is frame ground. 

You only need the "minus" lines.  Ignore (leave disconected) the "plus" lines.

 

 

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Thank you for the information

Thank you for the information.   

I was able to get the WiFi modem to talk in Proterm 3.0. I used a db9 screw down connector in the other end of a din8 where all the pins were attached to a wire I clipped off one end then made the db9 side.  

it appears based on a rs232 diagram I was able to connect 6 wires base on that spec.  

some pins like RI were not present on the apple side.  

 

I plugged in a rs232 breakout tester and it appears 4 lines are illuminated. Tx and Rx are low them flicker high when typing, etc. Dtr and cts are illuminated high.  

it does work but I want to make sure I should not see more. I configured the WiFi modem as a Hayes Smartmodem 9600  rts/cts. 

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The Apple IIGS doesn't do

The Apple IIGS doesn't do anything with RTS/CTS signals.

And you're right, there's no RI signal present on the IIGS, nor is there one on a Super Serial Card, which is the standard RS232 card for the Apple II.

 

You should be able to achieve 9600 baud sustained communications without errors.

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I use a WiModem232 with a

I use a WiModem232 with a IIgs and IIe, 9600 is generally fine. Because the WiModem232 is 25pin, I just used an off-the-shelf DIN-8 to DB25 cable. 

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I had purchased a (supposedly

I had purchased a (supposedly) modem cable off eBay but when I toned out the pins it had one pin attached to three pins on the modem side and another tied to two pins. Nonetheless it did not work with the modem. So I just bought and 8pin, all pins connected to the same on the other side , cut off one end and attached the wires to a 9pin screw down connector so there was no soldering.  

i am new to this cabling so I puttered around with it and bought some tools and eventually got it right on the modem

side.  

I am learning and now have a few tools from the experience. 

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baldrick wrote:The Apple IIGS
baldrick wrote:

The Apple IIGS doesn't do anything with RTS/CTS signals.

And you're right, there's no RI signal present on the IIGS, nor is there one on a Super Serial Card, which is the standard RS232 card for the Apple II.

 

You should be able to achieve 9600 baud sustained communications without errors.

I was going to make a cable for my IIe next that additional info is good to know.

 

Thank you for your help, I am learning a lot from this. 

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