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6522 based serial interface for IBM PC?

carlsson

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Last time when I went to pick up some more PET computers, I browsed around all the computer stuff everywhere: on shelves, in drawers etc. I found two PC related items (sorry, no pics) that I wonder if anything can be said about, or if they would be worth trading:

1. It looks like a serial port interface for 8-bit ISA bus, judging on the number of pins. What made look twice was that it has a MOS 6522 VIA chip. I know this is used for various applications including serial communication on different 6502 based systems, but was it commonly used on serial interfaces in the (IBM) PC world as well? There was one external connector, a male DB9. I thought all serial ports were DB25 back in the days of 8-bit ISA, if that was what it was. My other guess is that it is some early joystick interface for using Atari-style joysticks???

2. A 16-bit ISA floppy/IDE controller that also had headers for DRIVE 0 and 1, if I recall correctly. I have a vague memory of having seen that before, but I can't remember its use. Is this a bog-standard item that in untested condition isn't worth the shipping costs? Sorry, I didn't recall the brand.

Those were the only items directly aimed at the PC platform that I found at a brief look. Since there are a few Victor computers lying around, do those also have the ISA bus and the cards might be related to them? Considering a few boxes full of shrink-wrapped packs of 5.25" HD floppies, which neither Commodore PET nor Victor Computers used, I suppose the former computer store catered for local PC users as well, but in rather limited scale.
 
I brought it with me home. The most interesting (?) chips are SY6522 and MC6852P. The big grey blob (relay?) is stamped 6975 2 on the side. On the plate, there is a male DB9, a 3.5 mm jack and some odd jack I probably should take a picture of, since I can't describe it in words. The board is marked Handic Software 1066 K.
isa-serial.jpg

What is this most likely to be, a serial port? Modem? Atari-style joystick interface for IBM PC? Would it be worth something? Needless to say, I don't have anything to test it with, although I suppose it if is an 8-bit ISA card, it would physically fit in a 16-bit ISA slot too.
 
I don't know anything about the card, but I do have a correction for you that might make a difference. The 6522 is an I/O chip, but not a serial port. It has 20 I/O lines on it. Wikipidia has a good write-up on it:

http://en.wikipedia.org/wiki/MOS_Technology_6522

This could be a data acquisition board, or a controller board for a custom device. It is probably not a serial port or a modem as those would have used a UART (6551), not a 6522 type device.


Mike
 
Yes, I have a somewhat good idea of what a 6522 VIA (versatile interface adapter) is. For example in the VIC (and PET?) you have two such chips. Each chip has two ports, so it can handle a subset of the following: user port with eight data lines, keyboard/joystick, disk interface, tape interface and so on.

The user port is said to be electronically RS-232 compatible, but you need a small interface for converting the connector and signal. Indeed most higher quality interfaces uses a 6551 UART to allow faster transfer speeds, but I've found cheap designs without one, relying on the 6522 to do its job in perhaps 1200-2400 bps. Probably more circuits are required if you want to build a modem.

Furthermore, I found that MC6852(P) is a synchronous-serial data adapter, as opposed to the MC6850 asynchronous communications interface adapter (UART).

I wonder if the small jack is meant for external power or some remote control. In any case, it is mildly interesting and I could upload a higher resolution image if anyone wants.
 
Almost certainly modem + something??,

The transformer is probably to provide line isolation, the two opto isolators (6 pin chips) are possibly to give ring indication & do line seize (i.e. prepare to ring out) and the 28(?) pin chip with the crystal next to it in the middle-top is almost certainly the "modem" HOWEVER.....

I can't see the obligatory isolation zone around the "line interface" part &
it seems a bit over-the-top for a modem

Could it be either...

a really early modem that is pre-requirement for the isolation gap,

Just that I can't see the isolation gap in that shot,

or, as handic do a lot of radio comms stuff, something like a radio-data, or pager modem.
 
What's the frequency of the crystal next to 22-pin Sharp LR4101D chip? If it's 3,58MHz then the Sharp chip is probably DTMF decoder or generator, not modem.
 
After four years of searching, I have finally found what this card is. In a feature article in Swedish computer magazine Mikrodatorn, issue #4 May 1986, it is described as a Voice Management System (VMS) which was controlled from Basic. It could be used to connect a telephone line and use the PC like an combined answering machine and also add data to the computer by using the keypad on the callee's telephone. One of its uses was to remotely control computers without an operator. The Basic program would load and play pre-recorded sound clips to the caller and wait for responses. The system specs were 256K RAM, 15 MB HDD and "some knowledge in Basic programming". It was estimated 15 MB HDD would be enough for 1.5 hours of speech files. The retail price was 12995 SEK + VAT, about $1850 at that time.

As a matter of fact, I have about three more or less assembled cards plus another 2-3 bare boards. Probably my source worked as an assembly house for Datatronic, but ended up with a small surplus of cards that never found any buyers.
 
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