[Coco] Color computer these days... (source for 360K drives)

[Frank Swygert]

The HDS floppy controller is a really good one! That company made HD controllers, but they also made the floppy only controller for the CoCo. 

You can't use 5.25" 1.2M drives. Well, not easily. I believe some can be used as they have a jumper to control the speed (turn faster for 1.2M), but not all do, and there are read/write issues to contend with. As long as you follow specific procedures they work, but can be a hassle. 

1.44M floppy drives CAN be used, but only with genuine 720K disks. Those are hard to find nowadays! The drive senses the type media (720K or 1.44M) and adjusts speed accordingly. You can use a 720K only drive, and I think it will work with 1.44M disks, but not sure. 

Best of all, California digital still carries used/refurbished 180K and 360K 5.25" drives, and even has some 720K 3.5" drives. Prices are $9-$39. http://www.cadigital.com/cadigtl.htm. Click on floppy drives, scroll to the bottom. They carry a lot of the old 8" drives which should be of no interest at all! If you click on computers you will find that they still have Tano Dragons (copies of the CoCo 2) available for $45. I believe they bought out the remaining stock when Tano went out of business and have been selling them ever since. Must have received a LOT of them! I doubt they sell more than 3-4 a year now though. 


As for the "CoCo4", I like the software emulation model. Compact P4 computers with a couple PCI slots can be bought for under $100. Even an FPGA system board would cost over $200. A generic PC already has everything needed built in and is cheap. The only thing it lacks is the CoCo expansion connector, or something similar that is easily accessible. The Parallel port is close -- it's bi-directional and can be reprogrammed, but not under Windows (at least not easily). 

It wouldn't be hard to modify one of the existing DOS or Linux emulators to completely masks the OS. In other words, have it boot up in the emulator without the user ever seeing the native OS. There would need to be an "escape" button to get to the native OS for maintenance issues, but most needed operations could be on a menu that keeps the native OS invisible. Would be even better to make the emulator the OS -- but that would take a lot of work. Sort of like Apple going from PowerPC to Intel processors -- the CoCo could jump from 6809 to Intel. Since all the needed items are already on the board, the parallel port could be reprogrammed to operate as an I/O port for experimentation, maybe even emulate the CoCo expansion port -- or emulate a PIA board plugged into the CoCo expansion port. The later might be easier -- and PIAs are pretty easy to program from the CoCo. 

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Date: Tue, 09 Dec 2008 17:50:32 -0800
From: Michael Robinson <deemcr at robinson-west.com>

Worse, I searched for 360k disk drives and couldn't find any. I have two 360k disk drives that are shot.  
Can I cheat somehow and get away with using a modern 1.44 meg floppy drive as a substitute?  What if I can find a 720k disk drive, will that work?  My disk 
controller says hard drive specialists on it, but it doesn't 
control a hard drive.

-- 
Frank Swygert
Publisher, "American Motors Cars" 
Magazine (AMC)
For all AMC enthusiasts
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