Nice, reasonable person on ebay - not mine.

[+Nezgar]

On 11/28/2019 at 1:05 PM, BillC said:

I have one and prefer the 1050, which has more storage plus multiple upgrades available. The AT88-S1 I have is only single density, so the equivalent of an 810.

I wonder how many single-density only AT88-S1's are out there.. and if there would be enough that might justify any effort in replicating the double-density adapter board... Most of the AT88's I've seen people posting about in the last year or two have been double density capable. (Including my own)

 

Anyhow, I would be interested in a ROM dump from your single-density unit. The upgrade instructions for the DDA describe removing the ROM and replacing it, which virtually guarantees it has unique code for single-density only operation.

 

Cheers

[BillC]

3 hours ago, Nezgar said:

I wonder how many single-density only AT88-S1's are out there.. and if there would be enough that might justify any effort in replicating the double-density adapter board... Most of the AT88's I've seen people posting about in the last year or two have been double density capable. (Including my own)

 

Anyhow, I would be interested in a ROM dump from your single-density unit. The upgrade instructions for the DDA describe removing the ROM and replacing it, which virtually guarantees it has unique code for single-density only operation.https://yts.am/browse-movies/0/all/action/8/latest?page=5

 

Cheers

I doubt it has code not present in the DD version since that one would be capable of both SD + DD operation. Mine does have a daughter-board which I presume is the data separator, I determined SD only operation by failure to perform a DD format with SpartaDOS.

 

I acquired the AT88-S1 in a bundle on eBay about 10 years ago with my 1st 1200XL.

I'm not that concerned with it only being SD capable, I also have 2-810s with the same limitation.

I have other drives, Happy 1050/USD 1050/XF551, for DD floppy access.

 

[+Nezgar]

4 hours ago, BillC said:

I doubt it has code not present in the DD version since that one would be capable of both SD + DD operation. Mine does have a daughter-board which I presume is the data separator, I determined SD only operation by failure to perform a DD format with SpartaDOS.

As your ROM is likely missing DD functionality, which is why I'm interested in it. With enough dumps (which I'm up to about 3 or 4 now), and disassembly by folks like Phaeron, we might be able to map out the order of ROM releases, and see which are derivatives of which. Maybe yours is very similar to the first RFD ROM's, but with some flag set or code omitted to block DD commands...