[Coco] Disk controller summary?

[Rogelio Perea]

Torsten Dittel wrote:

> Which was the "best" floppy disk controller ever made for the CoCo?
> FD501? Disto? Burke&Burke? J&M (JFD)? Any votes? Could someone summarize
> which models have been available with which features?

Marty Goodman ran a very good article as a recap of CoCo disk controllers in 
a 1988 Rainbow Magazine... sadly my mags are like 2500 miles away so I can 
not pinpoint the month and I maybe mistaken on the year as it could be 1989. 
But from memory I remember clearly reading in more than one place that the 
best generic CoCo floppy controller was the one that bears the 26-3029 Radio 
Shack catalog number. This is (I think) the last Tandy/Radio Shack "long" 
pak controller, mine has a 1982 date stamped on the board, a 24 pin ROM 
socket and the MB8877 controller chip, no adjustable parts (pots) inside so 
everything's PLL. According to Marty's review, this was the most sought 
after controller by programmers. I have never had any issues with it as a 
user, not even after the fact that the card edge pads are not gold plated.

In my opinion, from the Tandy offerings, the 3029 mentioned above, the 
FD-501 and the FD-502 are the best. The FD-501 is packaged in a nice short 
pak and has the disctinct privilege of being the only controller from 
Tandy/Radio Shack that features gold plated connector pads; it also has a 24 
pin ROM socket and the WD1773 controller chip. The FD-502 I like probably 
because it was the last of the bunch to be offered by the CoCo creators, it 
comes with a 28 pin socket (good!) and the only thing I don't see as a 
selling point is that Tandy went back to the standard non gold plated 
connector pads. My FD501 has the WD1773 controller chip like the FD-501 and 
the board looks almost the same as the 501. Another miscellaneous aspect of 
the FD502 that I like is that the access to the holding screw is from the 
bottom of the unit and not on the top... on my other controllers I had to 
cut a small hole on the label in order to access the phillips headed screw.

>From the third party offerings, while I never owned one, I'd say that the 
Disto Super Controller II is the best of all (and that's including Tandy's 
offerings), it does the no-halt under OS9 and you can cram extra goodies in 
there because of the Disto Mini Expansion Bus (parallel printer port, RTC, 
SCSI...). This was/is the controller I alwas drooled over while reading the 
Rainbow and never managed to squeeze out the bucks to buy one. It ranks very 
high on my list when hunting around thrifth shops and ham fests :-). I did 
own a Disto Mini Controller, it was a very nifty and unpretending short pak 
controller, gold plated contacts and a 28 pin ROM socket, in fact I cloned 
the ROM it came with and stuck the clone in my FD502 on top of a Tandy 
Smartwatch... tight fit in the FD502 because of the height of all this 
piggybacking, I actually removed the 28 pin socket and installed the 
Smartwatch in it s place, then snapped the ROM on the Smartwatch "socket", 
that was the only way to make this fit in. The Disto ROM provided for 6ms 
stepping rate and second side access to the floppy under RSDOS.

There you have it, my $0.02 on CoCo disk controllers, let's see what the 
rest of the gang holds dear and close to their hearts!


-=[ Rogelio ]=-