While working on a couple Atari 1050 floppy drives found a weird upgrade board... What is it?

[VERAULT]

Doing some work on a couple ATARI 1050 Floppy drives I discovered an addon board. Here are some photos. Any idea what this thing might be? It plugs into the 6507 socket and the main board does NOT have the Tandon 188063-001K (mask rom?)

Weird thing is all the identifiers on the small board have been sanded off! You can see wear marks. Only the eprom has anything readable.





I have also attached a dump of the eprom on this board.

 

[Gary C]

Copy protection for something ?

 

[Timo W.]

Some generic floppy speeder. Probably a clone of the Happy 1050.

 

[VERAULT]

HAve any information on it? Does it need to be loaded or require software or does it just work as is? Reason I am asking is I am giving one away so I need to know as much about it first as possible.

 

[Timo W.]

These do just work. Also, they allow DD disks to be used. The chip above the EPROM should be the SRAM needed for that (track buffer).

 

[Bob-O-Rama]

Pulling strings from the ROM image you see:

2793/2797
VERSIONREV 2.31 3-16-86
COPYRIGHT (C) 1986 BY EMC
COPYRIGHT (C) 1986 BY DTI

Its probably a 1050 Duplicator - by Duplicator Technologies Inc

See http://www.oldcrows.net/~patchell/atari/duplicator.html

The final .ASM file linked in the page above includes:

;
DB '2793/2797 VERSION'
DB 'REV 3.10 '
DB '2-21-87
DB 'COPYRIGHT (C) 1986 BY EMC'
DB 'COPYRIGHT (C) 1986 BY DTI'

So its actually a tiny 6502 computer!

-- Bob

 

[VERAULT]

Yeah the 1050 drive has its own 6507 cpu.

 

[Timo W.]

So its actually a tiny 6502 computer!

Yes, most speeders use a full 6502. They are all pretty much the same: 6502 CPU, some SRAM, and an EPROM.

 

[VERAULT]

I couldnt tell you if it was a full 6502 or 6507 as the footprint of both chips exists but they sanded off identification.

 

[Timo W.]

The 6507 has only 28 pins instead of 40. So easy to tell apart.

On cheap speeders, you would re-use the 6507. But these were very limited.

 

[Bob-O-Rama]

The source is actually pretty interesting as you don't often see commented source for disk controller firmware. You could build version 3.10 and give it a firmware upgrade.

-- Bob

 

[Timo W.]

btw, if you have the drive connected with no disk in, it should auto-load the disk duplicator software stored in the speeder's ROM.

 

[VERAULT]

The 6507 has only 28 pins instead of 40. So easy to tell apart.

On cheap speeders, you would re-use the 6507. But these were very limited.

Im aware of that, but like I said the foot print of BOTH large CHIPS on the small board are 28 and 40.

 

[VERAULT]

btw, if you have the drive connected with no disk in, it should auto-load the disk duplicator software stored in the speeder's ROM.

It doesnt do that, I can assure you.

 

[VERAULT]

btw, if you have the drive connected with no disk in, it should auto-load the disk duplicator software stored in the speeder's ROM.

And it bit beyond my knowledge! but Im sure it would be a neat upgrade.

 

[Timo W.]

It doesnt do that, I can assure you.

Did you try with the lever down?

But not knowing that exact speeder, maybe that was a feature not yet present in 86/87.

 

[VERAULT]

I did not, but I can give that a try.

 

[VERAULT]

Did you try with the lever down?

But not knowing that exact speeder, maybe that was a feature not yet present in 86/87.

No change at all with the lever down. So I guess it does NOT have a builtin program. Too bad. That would have been a pretty cool feature in the early 80's