What are these Coco items?

[ianoid]

Two things that came with Coco stuff. One may be a Disk Drive adapter? The other is a switch, but I'm not sure what 4 pin DIN(?) this would be useful for?

 

Also came with a Symphony 12, which had no markings on the outside aside from the Speech Systems label but has 4 AY-3-8912 3 voice music synthesizer chips in it (last three. Fun!

[Bruce Tomlin]

4-pin plug is the printer port, RS-232 with one-way CTS handshaking, defaults to 9600 baud for LPRINT. It's completely bit-banged, so it isn't reliable to receive faster than 1200 baud. The Videotex cartridge actually used the video horizontal sync interrupt as a 25x clock to sample the input every scan line for a reliable 300 baud. At some point I rigged it up so that BASIC could use that code, but it really hurt performance.

 

It could also be used with a DLOAD server from a PC. I found some code I wrote a long time ago ('84 in asm and '96 in Pascal!) Last week I think I ran across the Coco that I used it with back in '96 (as a 2600 cart dumper), so I may tinker with it in C next week. Basically it would let me send a small BASIC program from plain text.

 

And that other thing is indeed a disk adapter. WDC1773 is a floppy controller chip.

 

Quad AY-3-8912s? Holy crap that's a lot of sound chips.

Edited October 28, 2019 by Bruce Tomlin

[linville]

As above, the 4-pin DIN is the CoCo serial port standard. The one with the WDC1773 is a floppy driver controller, apparently with 4 ROM sockets for alternative DOS ROMs.

 

The Symphony 12 indeed supported quad AY-3-8912 chips. If you might be interested in selling that one (separately or part of a lot), then please let me know. I would be interested.