Jump to content
Dropcheck

Gauging interest New XF551 Drive mainboard

Recommended Posts

Well I think this might need to move to an official thread.... :)

 

So I did.

 

My purpose in doing this is to prolong the life of the XF551 drive in as original form as possible. Drive mechs can be scrounged from surplus houses, but the board is uniquely Atari. Where it was reasonable I improved on the board with minor improvements. I am not an engineer so you won't find any golly gosh darn whiz bang fancy do dads.

 

Warning: No arguements about SIO this or that. It is what it is. I have plenty of those other devices and use them. Their merits belong in another thread.

 

I've mocked up a 3d rendering of what the board should look like. Some of the parts eagle 3d and povray just don't understand but at least the outline is there.

 

It's about 80-90% done. There is one feature that I would like to add but until I can confirm approval I am not going to talk about it yet.

 

In general preliminary specs are:

 

Board Size: 150mm x 100mm (about 2 inches(50mm) less length than original)

Should be a dropin replacement for current motherboard, you'll use the same case.

Uses an external power supply with apropriate connector (Not Atari power supply)

All chips will be socketed

Will have builtin 4in1 OS switching capability, you'll supply the burned eprom based on your drive mech

Will have an extra internal SIO connection for future options

Uses standard 3 1/2 and 5 1/4 floppy IDC data and power connectors

Price = ? depending on number ordered and paid for

 

There is some question about availability of hard to find chips ie WD1772, 8040/8050, 27128 and the 8.3333 MHz clock. I have a small stash for a limited # of boards. Currently Ebay and Best Electronics is the best source. I could offer the board sans those chips or a bare board.

 

I'll know more when I've debugged a prototype. Hopefully I can finalize the board layout in the next week and then send it out to have the proto made.

 

XF551NewMB6.jpg

Share this post


Link to post
Share on other sites

I'd be interested in one populated board, less the major I.C.'s.

 

-Larry

 

Edit: could you amplify your comment about the 4-in-1? Resistors, connecting points will be on the board to use a '512 for multiple OS?

 

Make that two, less the major I.C.'s

Share this post


Link to post
Share on other sites

Interested in at least one populated board, possibly a bare board too.

Share this post


Link to post
Share on other sites

For us who don't own an XF551, what would be needed in addition to this board and a mech to build a drive from scratch?

Share this post


Link to post
Share on other sites

Yes I would like to have one...Populated.

 

Are you going to have a source to recommend for the powersupply..?

Share this post


Link to post
Share on other sites

I'll take two with all the components, and probably another 4 bare. Depending on price ofcourse. If you during the process discover a new source for all those needed chips, I'll probably want more boards with all the components.

 

Very interesting.

 

One more question about XF551 ... am I right that this drive does not have any belts? So the mechanism might last longer than 1050's with belt?

Share this post


Link to post
Share on other sites

Could someone explain the OS in a floppy drive board thing to me? I'm not quite getting

the "big picture" there, thanks!

Share this post


Link to post
Share on other sites

The 8-bit peripherals are "semi intelligent", ie they receive commands to do complex operations like read sector, format, etc.

 

Where on other systems the host might do all the grunt work like telling the controller what to do (seek etc), the peripheral does it itself which leaves the host (Atari) to go about doing other stuff (although using OS SIO it just idles while the bytes fly in).

Share this post


Link to post
Share on other sites

I would like 4 boards, I have 4 wd1772 chips, and 2 8040 chips I can reuse. The rest I will need. I see the 27128 chips are cheap but I have no way to burn the eproms.

 

Robert Miller

Edited by venom4728a

Share this post


Link to post
Share on other sites

For us who don't own an XF551, what would be needed in addition to this board and a mech to build a drive from scratch?

 

The case of course and power supply. Depending on how populated the board is you might need ICs Top and bottom case can be had from Best Electronics. ~$40.00 or scrounged. Power supply from here http://rover.ebay.com/rover/1/711-53200-19255-0/1?ff3=4&pub=5574883395&toolid=10001&campid=5336500554&customid=&mpre=http%3A%2F%2Fwww.ebay.com%2Fitm%2F190391450076%3FssPageName%3DSTRK%3AMEWNX%3AIT%26_trksid%3Dp3984.m1497.l2649 Screws and nuts of course

Share this post


Link to post
Share on other sites

Yes I would like to have one...Populated.

 

Are you going to have a source to recommend for the powersupply..?

 

I'll be using this as a source at least for the proto board. http://rover.ebay.com/rover/1/711-53200-19255-0/1?ff3=4&pub=5574883395&toolid=10001&campid=5336500554&customid=&mpre=http%3A%2F%2Fwww.ebay.com%2Fitm%2F190391450076%3FssPageName%3DSTRK%3AMEWNX%3AIT%26_trksid%3Dp3984.m1497.l2649%23ht_3413wt_950 As long as it has the same connector and wiring and power specs other power supplies may work as well.

Share this post


Link to post
Share on other sites

I'll take two with all the components, and probably another 4 bare. Depending on price ofcourse. If you during the process discover a new source for all those needed chips, I'll probably want more boards with all the components.

 

Very interesting.

 

One more question about XF551 ... am I right that this drive does not have any belts? So the mechanism might last longer than 1050's with belt?

 

I believe so. At least I don't see any belts on the drive mech from my disassebled XF551. Last longer I don't know. I've still got several 1050s going strong after 35+ years. It all depends on how hard you use them. :)

Share this post


Link to post
Share on other sites

From XF-551 schematics I see we can reuse wd1772 and 8040 or 8050 if they are still functional. I found a Atari 1050 schematic and it looks like no chips that we can reuse for this project, still possible to reuse the SIO connectors. :)

 

Robert Miller

 

 

Share this post


Link to post
Share on other sites

From XF-551 schematics I see we can reuse wd1772 and 8040 or 8050 if they are still functional. I found a Atari 1050 schematic and it looks like no chips that we can reuse for this project, still possible to reuse the SIO connectors. :)

 

Robert Miller

 

I'd hate to see a 1050 scavenged. :_( Better would be a 1030 modem or 1010 tape drive. :) Better still would be Best Electronics. I think they still have some in stock.

Share this post


Link to post
Share on other sites

 

 

I'd hate to see a 1050 scavenged. :_( Better would be a 1030 modem or 1010 tape drive. :) Better still would be Best Electronics. I think they still have some in stock.

 

:) I do agree! I have 2 that are in nonfunctional condition, I have not spent a lot of time trying to figure out what is wrong with them. I do know its something on the board, I tested both the drive mechs in another drive and they worked fine. I also swapped some of the chips(not all) and the chips worked too. I put them on the back burner to fix another time. I still have several good working 1050's.

 

I am going to get some Retro Brite mixed up and clean my XF cases, and probably a few other xl's cases that need some tlc.

 

Robert

 

 

 

 

Share this post


Link to post
Share on other sites

Hey Lenore, I purchased several of these Atari XF551 Controller boards about 10 years ago from Mike Mallory (aka 8bitdomain). As I was told then they are 100% compatible with the original XF551 floppy drive and will work with 5.25",3.5" floppy drives and 3.5" slimline/laptop drives (connector needed). Hyper speed bios accelerates drive access faster than Happy or 1050 Doubler drive. Drive capacities from 90k thru 720k. The board size is 3.5" x 4.5" (smaller than a 3.5 floppy drive). Requires 5vdc-regulated power.

 

My interest will be in a couple of unpopulated boards.

 

Mike

 

gallery_16380_756_96073.jpg

Share this post


Link to post
Share on other sites

I have both a stock XF and a 3.5" XF. Will this board work for the 3.5" XF?

If so, I'll get 2.

Share this post


Link to post
Share on other sites

I'm interested in 1 fully populated board.

 

Regarding parts:

 

- 8 1/3 MHz can be generated by dividing 25 MHz by 3. IIRC some 74HTCidontknowanymore can divide by three

 

- WD1772 can be salvaged from old STs and sometimes bought new on epay, although I suppose Best is a better source

 

- regarding those 8040/8050, I still wonder if old AT/386/486 keyboard controllers are suitable. They are pre-programmed but can be made to work with an external ROM or EPROM.

 

 

Edit: STOP! What firmware version do these boards get? The version that can only run on NTSC systems or the one that can run on PAL and NTSC?

Edited by 31336haxx0r

Share this post


Link to post
Share on other sites

I'll take one.

 

Would be really cool if these could fit into and SF354/314 case.

Share this post


Link to post
Share on other sites

I'll take one so long as it's cheaper than a replacement board from B&C

 

If it takes the 3.5 mech then I'll probably buy two

 

Share this post


Link to post
Share on other sites

I'd be interested in one populated board, less the major I.C.'s.

 

-Larry

 

Edit: could you amplify your comment about the 4-in-1? Resistors, connecting points will be on the board to use a '512 for multiple OS?

 

Make that two, less the major I.C.'s

 

 

Since all the OSes for this drive are only 4k, there not really any reason to go beyond 27128. That gives you at least four slots. You get to pick which four based on your drive mech. Need a different four because you've changed the drive mech, reprogram the eprom and pop it back in, or keep a second one handy and pre programed and pop it in. :)

Share this post


Link to post
Share on other sites

I'm interested in 1 fully populated board.

 

Regarding parts:

 

- 8 1/3 MHz can be generated by dividing 25 MHz by 3. IIRC some 74HTCidontknowanymore can divide by three

 

- WD1772 can be salvaged from old STs and sometimes bought new on epay, although I suppose Best is a better source

 

- regarding those 8040/8050, I still wonder if old AT/386/486 keyboard controllers are suitable. They are pre-programmed but can be made to work with an external ROM or EPROM.

 

 

Edit: STOP! What firmware version do these boards get? The version that can only run on NTSC systems or the one that can run on PAL and NTSC?

 

Correct me if I am wrong as I only have the US schematics, but the eprom that you supply is what determines whether it's PAL or NTSC.

Share this post


Link to post
Share on other sites

I'll take one.

 

Would be really cool if these could fit into and SF354/314 case.

 

Would be a different thread and a different board. Maybe for another time or a project for another person. ;-)

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

  • Recently Browsing   0 members

    No registered users viewing this page.

×
×
  • Create New...