Apple //e SuperSerial card or similar

[ajross]

Hi - I'm after an RS232 (serial) adapter card for an Apple //e, ideally with a 16550(A?) UART, but 8250 will also be OK.

Would rather not have to buy one from the USA, can't find any here in NZ on TradeMe.

Let me know if you have one- much obliged!

[Gibsaw]

Hi - I'm after an RS232 (serial) adapter card for an Apple //e, ideally with a 16550(A?) UART, but 8250 will also be OK.

Aj, unless you have something very special in mind, I think you might be mixing your genre's there. The 16550 vs 8250 issue was a buffer length difference pertaining to >28.8k modem thing (i.e. 115k DTE speed) from the 486 era.

The UART is not really your limiting factor on the IIe. I've read fairly well optimised ASM serial code that tops out at about 56kbit with even a basic demonstration loop. Admittedly, bit banging is going to be slower than a byte UART, but I suspect you would struggle to saturate even an 8250 on the 1MHz 6502.

In any case, I don't think I've ever seen a serial for the Apple II using the IBM PC style (byte) UARTS, so probably no software will support it.

UPDATE: The closest thing I've seen so far to a 16550 UART on an Apple II is someone suggesting it might be possible to build one.

The regular Apple "super serial" is pretty much universally supported and capable of a wide speed range. ADT Pro at 19.2kbit will fill a 140k floppy in a matter of seconds. What are you wanting to do?

[ajross]

Yes, perhaps I am getting my wires crossed. I want to do two things:

1) Connect my Platinum to my linux box (and potentially soon raspberry pi) via Serial Telnet connection.
2) Copy disk images to and fro the // via ADT.

It's been many years since I did this, so perhaps I imagined that I had a serial interface at 16550AF (but maybe that was the IBM PC/XT). I remember that the 8250 was not buffered, and the 16550(minus the A/AF) was also not buffered too, which led to slower speeds and more errors. The 16550 also gave speeds higher than 19200bps which was nice if you wanted to transfer things a little quicker. No matter, if you reckon the Apple SuperSerial will do the job then I'll change my request to simply "I would like to buy a SuperSerial card" or a compatible one that can do the above 2 tasks without issue.

Thanks again!

[Gibsaw]

Yeah, I thought that would probably be your objective. The Apple "super serial" or compatible (based on the MOS6551) is what you'll want.... It will "just work" and it will fill a disc in seconds.

Apple II comms programs and ADT pro directly support the card, and just as important, it's directly supported by it's firmware in the usual Apple II manner, so PR# and IN# work with minimal fuss for serial type comms.

It's a valid idea to use a byte UART on the IIe for something application specific. It would be a bit faster, and others are proposing doing it for SLIP type applications, although it's probably not worth the work when the "uthernet" (ethernet) card is already supported by contiki and the like.

[ajross]

So, the question is - does anyone on this forum have a Super Serial card for sale?

[Gibsaw]

I don't really have a spare one at the moment myself, and they don't really come up by themselves on trademe. They are reasonably common to find inside a IIe these days. Because of disk images and the internet you're far more likely to find one inside a machine now than back in the day. But unless you pick one up by buying a IIe, then I'm afraid ebay is probably your best bet...

The good news is, they're really common. Don't let anyone tell you they're "RARE!!!!!!!!"

... and one more thing. Don't let anyone sell you one without the DB25 external connector tail that attaches to the case. So many people either rip these out of machines to sell and leave the DB25 connector tail attached to the casing, or worse... you'll find them selling the "tail" separately. This is just a rip-off. Don't stand for it. Hassle them.

Unless you like soldering DB25 to header type cables, the card is sod-all use without it. Unless you can get one separately, don't pay more than a few dollars for a card without one.

[ajross]

Cheers Gibsaw, I'll ebay away. I found some in the USA last week when I was looking around, still pricier than I remember 3-5 years ago, but then again, obviously the 'vintage' computer world is bigger now so more demand.

I also used to have a Utherboard, with Contiki software so I could get my //e on the Internet, I spoke to the guy from a2central and he is apparently making a new batch of utherboards so I've put my name on the list for one of those.

[Gibsaw]

There is another option too, which while slightly pricier is definitely the better option. The CFFA3000. I have one of these, and they are really good.

Then transferring software is a matter of copying to a USB stick.

[tezza]

I've got a couple of Super Serial cards but none are spare unfortunately.

I will second Gibsaw in the use of the CFFA 3000. Expensive, but a great piece of technology, especially with a IIGS.