Atari 820 Drive... or is it?

[Timothy Kline]

Alright, I seem to have come across another odd bird during one of my Atari 8-bit binges.

 

This time, it involves an Atari 810 drive that claims itself to be an 820-- which we know is a printer from Atari.

 

But hey, let me just show you the pictures, and then I'll wait for someone to tell me what I should try next with this...

 

Thank you, in advance!

 

--Tim

[Brentarian]

Is there a serial# sticker on the bottom?

[Timothy Kline]

Is there a serial# sticker on the bottom?

 

Unfortunately, no. It looks like the bottom case was painted... white, of all colors. O.o

[Rybags]

Does this drive have a top half?

The 820 printer looks like it uses an identical bottom case piece as the 810.
My guess for what you have is that it's just something modified by an owner - actuall the case stuff is probably irrelevant - my guess would be it's just (in incomplete) normal 810 with the 820 sticker applied.
Does the drive itself have anything special like custom firmware?

[Timothy Kline]

Some additional pics...

 

--Tim

[Timothy Kline]

Does this drive have a top half?

 

The 820 printer looks like it uses an identical bottom case piece as the 810.

My guess for what you have is that it's just something modified by an owner - actuall the case stuff is probably irrelevant - my guess would be it's just (in incomplete) normal 810 with the 820 sticker applied.

Does the drive itself have anything special like custom firmware?

 

 

I was thinking the same about the bottom case of the 820 being used here. I added some additional pics that seems to show that the person took the time to make notes while they were inside. Not sure how I would go about checking the firmware, beyond seeing the "E" ROM I pictured earlier.

 

Suggestions?

 

--Tim

[tschak909]

That's the same rev E. rom that Owen Rubin has been talking about, for years. It has all sorts of little goodies in it (think of it like an early Happy of sorts)

 

-Thom

[Timothy Kline]

That's the same rev E. rom that Owen Rubin has been talking about, for years. It has all sorts of little goodies in it (think of it like an early Happy of sorts)

 

-Thom

 

How do I utilize it, software-wise? Is there a place to see the features?

 

--Tim

[tschak909]

No idea. That's a question that everybody who would know has long since forgotten, as that particular ROM revision was done entirely inside Atari, and never officially released. The only reason I know about it is from talking with Owen Rubin in the past, and him mentioning it again in one of the latest Antic Podcast interviews.

 

-Thom

[Bryan]

Has E been dumped?

[Timothy Kline]

Has E been dumped?

 

I would be the last person to know the answer to that one. I can say that this one hasn't been dumped since... well, I've never done a chip dump before. O.o

 

--Tim

[Defender II]

Any more info on the 'E' ROM functions? Let me know if you get it dumped.

[ijor]

810 firmware rev E is here: ftp://ftp.pigwa.net/stuff/collections/atari_forever/ROM/Rom%20-%20OS/DRIVE/REVE810.016

 

To be honest, I never paid attention to this version until reading this thread. Wasn't aware that there was a special version.

 

At quick glance, it has at least one goodie. Command $20 let you upload 128 bytes and run custom code inside the drive!

Also the firmware seems to be signed by Dave Staugas.

[tschak909]

810 firmware rev E is here: ftp://ftp.pigwa.net/stuff/collections/atari_forever/ROM/Rom%20-%20OS/DRIVE/REVE810.016

 

To be honest, I never paid attention to this version until reading this thread. Wasn't aware that there was a special version.

 

At quick glance, it has at least one goodie. Command $20 let you upload 128 bytes and run custom code inside the drive!

Also the firmware seems to be signed by Dave Staugas.

 

Yup, the E firmware was highly prized in Atari, as it was used to make..... "backups" .

 

-Thom

[ijor]

Yup, the E firmware was highly prized in Atari, as it was used to make..... "backups" .

Interesting. No Happy or Archiver allowed onsite? jaja

 

And where is the software to make the backups with that firmware?!

[orubin]

There is an advanced DOS version floating around that will add some functionality. Most of the changes were internal as well. Like formatting blank discs with a different sector structure. The new structure was designed to allow the next sector to be just approaching the readwrite head so that there was MUCH less wait when reading and writing the disc. It also allowed a track at once read and write which let you do a disc copy that got around most copy protections at the time.

 

Im sure with a bit of searching you will find a DOS version that works. Also I have no idea why it would identify as an 820 unless the serial board has been replaced. It is possible (do not recall) that the serial board has a way of identifying the device.

 

A better answer would require more digging. After all, that was 40 years ago I worked on that.

-Owen-

Edited August 4, 2016 by orubin

[orubin]

Looking at your pics, it seems to me that an 820 sticker was just placed on the drive. I would ignore that as someone being silly.

[Timothy Kline]

Looking at your pics, it seems to me that an 820 sticker was just placed on the drive. I would ignore that as someone being silly.

 

Could be. Someone earlier mentioned that the 820 printer and the 810 case are interchangeable. Previous owner may have did something to the original case that led to the exchange. Me, it just makes for an easy way to identify this curious 810 drive from my other 810 drives.

 

--Tim

[Timothy Kline]

There is an advanced DOS version floating around that will add some functionality. Most of the changes were internal as well. Like formatting blank discs with a different sector structure. The new structure was designed to allow the next sector to be just approaching the readwrite head so that there was MUCH less wait when reading and writing the disc. It also allowed a track at once read and write which let you do a disc copy that got around most copy protections at the time.

 

Im sure with a bit of searching you will find a DOS version that works. Also I have no idea why it would identify as an 820 unless the serial board has been replaced. It is possible (do not recall) that the serial board has a way of identifying the device.

 

A better answer would require more digging. After all, that was 40 years ago I worked on that.

-Owen-

 

Thank you for contributing to the topic! Especially enjoyed your interview with Kevin Savetz, where you mentioned some of the history behind ROM E.

 

I'll have to get it to read a disk, though, before I can test the DOSes I've collected through the years. My day job has been keeping me busy these days, unfortunately, leaving very little time for my Atari tasks. O.o

 

If I might ask, is the ROM E its own, or were there modifications that need to be made to the sideboard to accommodate it? My gameplan is to take the ROM chip and put it into a separate working 810 drive that I have, and just use it out of that 810.

 

--Tim

[orubin]

 

Could be. Someone earlier mentioned that the 820 printer and the 810 case are interchangeable. Previous owner may have did something to the original case that led to the exchange. Me, it just makes for an easy way to identify this curious 810 drive from my other 810 drives.

 

--Tim

 

Whatever works. Could be why the sticker was changed originally.

 

Note that the drive will work normally with Atari DOS. And if you format a drive, I believe you will get the new format just because that is what the drive does. You will notice it is MUCH faster on any drive with a newly formatter floppy.

 

Cheers,

-Owen-

[Timothy Kline]

 

Whatever works. Could be why the sticker was changed originally.

 

Note that the drive will work normally with Atari DOS. And if you format a drive, I believe you will get the new format just because that is what the drive does. You will notice it is MUCH faster on any drive with a newly formatter floppy.

 

Cheers,

-Owen-

 

Thank you, Owen!

 

If I understand you correctly, I can format a diskette with the ROM E to gain the benefit in speed, *and* that benefit will be reflected on stock drives, too, without the need for ROM E by simply using the diskette that has been reformatted?

 

--Tim

[Shawn Jefferson]

This sounds like "sector skew", which I believe some of the 1050 enhancements could also do, but mostly it wasn't used much from what I remember, since while it could speed up disk operations on one type of drive, another might end up being slower. Once we all had Happy drives, we were reading a track at a time anyway.

Edited August 7, 2016 by Shawn Jefferson

[BillC]

This sounds like "sector skew", which I believe some of the 1050 enhancements could also do, but mostly it wasn't used much from what I remember, since while it could speed up disk operations on one type of drive, another might end up being slower. Once we all had Happy drives, we were reading a track at a time anyway.

The US Doubler 1050s had the ability to format a floppy in a special UltraSpeed sector skew, which reduced time waiting for the next sector when using UltraSpeed(~56K) transfer speed. This drive upgrade didn't have a track buffer, but was much less expensive than a Happy 1050 board at the time.

[orubin]

 

Thank you, Owen!

 

If I understand you correctly, I can format a diskette with the ROM E to gain the benefit in speed, *and* that benefit will be reflected on stock drives, too, without the need for ROM E by simply using the diskette that has been reformatted?

 

--Tim

 

Yes, you should see some speed up even on standard drives. The order of the sectors was renumbered in the formatting on the E-Drive. When ANY drive reads the disk, it looks for a track and sector number. When reading (or writing) a track, often it reads (or writes) the tracks in numerical order. The old sector was just in order, 1, 2, 3, 4, 5... The problem is, when you read sector 1 and then send its data to the computer, sector 2 is already past the read head, and you have to wait for it to come all the way around again. BUT, if you put the sectors in a different order, one that will let the next numbered sector be just approaching the head when needed, then the next data is read very quickly, and you get a speed up.

 

So, try this: Format a new disk on the E drive. Now do a copy from an old disk to the new one. Then put the new one in the old drive and see if it works better. It should.

 

Let us know.

 

-Owen-

[ijor]

 

Yes, you should see some speed up even on standard drives. The order of the sectors was renumbered in the formatting on the E-Drive. When ANY drive reads the disk, it looks for a track and sector number. When reading (or writing) a track, often it reads (or writes) the tracks in numerical order. The old sector was just in order, 1, 2, 3, 4, 5...

 

I think the slow sector interleave was produced only by a very old 810 ROM (rev B, if I'm not mistaken). The more common 810 official ROM, rev C, already has a fixed, faster sector order. As far I can see, 810 rev C, 810 rev E, and 1050 ROM, all format tracks with the same interleave (sector order):

 

1,3,5,7,9,11,13,15,17,2,4,6,8,10,12,14,16,18

 

It would be nice if somebody has rom B and can dump it. Should have a different part number.