fall@ektools.UUCP (Jeff Fall) (02/16/90)
Hello, This is a plea to any CoCo 3 users who have wanted to expand their configuration only to find the expansion medium, the `Multipak' bus interface scheme marketed buy RS discontinued three years ago. I recently purchased the Burke & Burke HD interface card and software, a controller for MFM type disks and an ST251 Hard drive. After migrating from the MS-DOS workd, (and a hard disk), I didn't want to jump back 10 years into the floppy disk days when I was working with CPM. I have heard about a Multipak called the `Export' but I have been unable to find it. Instead, I am about to build my own Multipak, but I'm not sure of the addressing scheme or distribution of interrupts. If anyone is familiar with the multipak wiring and can send me the details on how the slots differ, I would really appreciate it and begin to build one. Thanks in advance, Jeff Fall Eastman Kodak Company, 716-726-0286
knudsen@cbnewsd.ATT.COM (michael.j.knudsen) (02/17/90)
You can now buy a sort of MultiPak from a new little company called HawkSoft. I think they advertise in The Rainbow, the Coco magazine. Price is around $80 or so. Much smaller than the old RadShack job, and only 3 slots, not four. If you can't find HawkSoft (in the Chicago area, code 312 or 708), try Howard Medical Co. (in Chicago, area 312 for sure). -- Mike Knudsen knudsen@ihlpl.att.com (708)-713-5134 "If you cut out drinking, smoking, steak, and sex, you may live 5 years longer -- if you want to."
djh9381@ultb.isc.rit.edu (D.J. Halko) (02/20/90)
Building all those neat little decoder circuits is not really needed in the multipak... Anyone building a multipak would probably be beter off just making it a buffered 4 or 6 slot Y cable... My personal opinion.. David J. Halko
ror@grassys.bc.ca (Richard O'Rourke) (02/20/90)
In article <2253@ultb.isc.rit.edu>, djh9381@ultb.isc.rit.edu (D.J. Halko) writes: > Building all those neat little decoder circuits is not really needed in > the multipak... > > Anyone building a multipak would probably be better off just making it a > buffered 4 or 6 slot Y cable... > > My personal opinion.. > David J. Halko I recommend that anyone thinking about constructing either of these monsters acquire a copy of the Feb. 85 issue of Rainbow magazine. It has a good article on the operation of the Multipak. I dislike the idea of a buffered cable somewhat more than I dislike the Multipak, neither strikes me as very good. I do have a Multipak though.
rh2y+@andrew.cmu.edu (Russell E. Hoffman, II) (02/20/90)
There is yet a third alternative that does work and is easy to do. Just use a simple Y-cable with no buffering. The trick is that you replace to 6809 about once a year, but at 2 or 3 bucks a pop, its not too bad, depending on how you look at the situation. The deal with the rs232 pack is you remove the ROM, which you don't need if you're using OS9, anyway. The problem isn't port addressing, its that the VIDEOTEX ROM in the cartridge is at the same address as Disk ECB. If you remove the rom from the cartridge and use the OS9 driver, you'll be pretty happy. And, while I don't really recommend the Y-cable idea I mentioned above, it will work rather nicely if you only have two cartidges maximum on the cable (I.E. a disk controller and an rs-232 pak) I run my PBJ Word-pak this way, and I've only had to replace the 6809 once, and I'm not even sure the Y-cable was the cause of the failure. Russ Hoffman Carnegie Mellon University rh2y+@andrew.cmu.edu ----------------------------- "<catchy quotation>" [ --<author name>]