Serial Interface and Super Serial Card Issues: no SSC prompt

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Last seen: 13 years 9 months ago
Joined: Feb 17 2008 - 12:45
Posts: 195
Serial Interface and Super Serial Card Issues: no SSC prompt

I am having some issues with both my Serial Interface and Super Serial Card.

Set-up: 1978 Apple II non-plus with 16K language card in slot 0 and disk controller into one of the right slots (can't remember which). Computer boots fine and functions perfectly. Has upgraded ROMS.

Apple Super Serial Card (1981 / C variant, kept stored in a static free bag for 15 years by the previous owner). Arrow on jumper points up for modem use. Setting on the SW Dip switches are as per the ADTPro website. Super Serial card is in slot 2.

Super Serial Card is connected via a RS232 to USB cable to my MacBook Pro OS X laptop.

On the Apple II, at the "]" prompt, I type IN#2
After that when I try or there is no response, I do not get the SSC prompt. My Cntrl function is OK because the Bell function works.

I have tried inserting the SSC into another slot 3 and typing IN#3 and then Cntrl A or Cntrl I, still no SSC prompt. Also tried other combinations of Cntrl and same result. I have tried the above after booting DOS 3.3 and get the same result.

When I type PR#2 or PR#3 the computer hangs and needs to be RESET.

When I use the Apple Dealer System tester to test my card it gives me the message "Unable to match code, replace the ROM chip in PROM 7, power on and re-test". Similar "replace chip" message happens when I test the 1978 Serial Interface card.

What should I do to get a SSC prompt?
Is there a way to test the 1978 Serial Interface Card without using a printer?

Thanks for your help, especially for reading through my long email (I wanted to be as informative as possible)


Last seen: 7 years 10 months ago
Joined: Jul 16 2006 - 17:30
Posts: 81
Let's see, the SSC is set to

Let's see, the SSC is set to "modem", and you have connected the SSC to your Mac using an RS232 cable. Is it a straight-through cable? If so, it won't work. You need either to change the SSC to "terminal", OR get a crossed ("null-modem") cable.

Either way, you could just try and disconnect the RS232 cable and see if you can get the prompt. It shouldn't require more than "IN#2" and then Ctrl-A, I think.

But it does sound like the SSC ROM is not functioning correctly. Have you tried re-seating all the IC's on the SSC, in case there is oxidation on the pins?

Another idea is to test whatever IC's you can test. Put them on an experiment board, and test the functionality. You can do this to the ROM too, to a minor extent.

BTW I think you can test the SSC by wiring it to loopback mode, i.e. connect the Tx signal to the Rx. Then do "IN#2" and "PR#2", and try typing something. It should echo back everything you type. Then disconnect the loopback wiring, and check that there is NO echoing of whatever you type...

Last seen: 13 years 9 months ago
Joined: Feb 17 2008 - 12:45
Posts: 195
error in original post: jumpe

error in original post: jumper arrow points DOWN towards "terminal"

Last seen: 15 years 6 months ago
Joined: Jun 24 2008 - 13:23
Posts: 6
same problem

Hi Arun,

I have exactly the same problem. I made a test with ADT and a PC and the SCC seems to work properly (but as far as I understand, ADT does not use the SCC firmware). The only thing that seems not work is the SSC firmware. I used the monitor to do a disassembly of the SCC Rom, and the code looks axactly the same like is printed in the SSC manual. I also had a look to the IO_SEL signal (with a oscilloscope) on the internal apple bus. In normal operation the IO_SEL signal is present but as soon as I do a IN#1 (1 is the slot of my SSC) the IO-SEL stops and the only thing I can do is to reset my apple. If you have found a solution it would be nice to get a reply from you.


Last seen: 13 years 9 months ago
Joined: Feb 17 2008 - 12:45
Posts: 195
I reseated all the non-solder

I reseated all the non-soldered chips on the SSC.
Also changed the position of the switches on the SW1 and SW2 box (I was incorrectly using the inverse/opposite of the correct settings for ADT).

Now I get the SSC prompt! Hooray - the genius of reseating. I wonder how many Apple II computers and related cards must have been thrown out by users over the last 30 years who were unaware about the reseating trick.

A2forever's picture
Last seen: 7 years 1 week ago
Joined: Dec 20 2003 - 10:38
Posts: 226
Good For You!

Glad to hear that you got your Super Serial Card issues fixed. Was this with the card I sent you? The original Super Serial Card? Or was this one of the newer ones the Super Serial Card II? I have had great luck using the Super Serial Card II with all of the II+ and IIe's that I have , along with my IIC , the IIC is great because I can just plug into the modem port of the IIC with a null cable and hook the null cable into a High Speed USB Adapter and plug it into any of my USB connections on my Laptop! Using ADT works awsome! The only thing I have not tried yet , and I want to , is hook up to my IIC+ and try transfering @ the IIC+'s high speed that it outputs at! Not sure if this would be critical at sending the data correctly at that speed , but the normal write speed would be the same. Any how just wanted to say that's great that you got everything up and running!

Patrick A.
Las Vegas, NV.

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