Atari XF-551 ROMs

[macsonny]

Hi All,

 

I recently was helped by a number of very kind people to get my XF-551 floppy drive working by replacing the main ROM.

 

I've since bought my own EPROM burner and made a few on my own ROMs including a HYPROMA and HYPER+ XF.

 

I was just wondering if there are any other ROMs floating around for the Atari XF-551 floppy drives I can try out?

 

Thanks

 

Sonny

[+MrFish]

Here's what I have.

 

I'm not sure what some of them do. My familiarity is with the 7.7 rom, which is the final Atari release, and the HyperFX roms. Maybe somebody else can chime in and explain what the others are.

 

Atari XF551 - HyperFX (A) [5.25 inch.] {2D2BE7C2}

Atari XF551 - HyperFX (B) [3.5 inch.] {E6D8F679}

Atari XF551 7.7 [NTSC-PAL] {38B97AE3}

Atari XF551 T80 (3.5 inch. 720kb) {0E117428}

Atari XF551 Turbo {3852A8D4}

 

XF551 ROMs.zip

 

[macsonny]

38 minutes ago, MrFish said:

Here's what I have.

 

I'm not sure what some of them do. My familiarity is with the 7.7 rom, which is the final Atari release and the HyperFX roms. Maybe somebody else can chime in and explain what the others are.

 

Atari XF551 - HyperFX (A) [5.25 inch.] {2D2BE7C2}

Atari XF551 - HyperFX (B) [3.5 inch.] {E6D8F679}

Atari XF551 7.7 [NTSC-PAL] {38B97AE3}

Atari XF551 T80 (3.5 inch. 720kb) {0E117428}

Atari XF551 Turbo {3852A8D4}

 

XF551 ROMs.zip 17.29 kB · 2 downloads

 

Thanks! Which is the best ROM in your opinion?

 

[macsonny]

Also, are these ROM files for 65kb EPROMs?

[sup8pdct]

Would like to see the dump of the 7.4 rom you have please.

 

James

[macsonny]

55 minutes ago, sup8pdct said:

Would like to see the dump of the 7.4 rom you have please.

 

James

Here you go.

 

 

XF551 v7.4.rom

[sup8pdct]

As i thought, the 7.4 doesn't have the speed corrections the latter ones do. No wounder it didn't work properly.

 

James

[xrbrevin]

On 7/20/2022 at 9:32 AM, macsonny said:

Also, are these ROM files for 65kb EPROMs?

the ROMs are 8k in size so try a 2764 or 27C64

[macsonny]

50 minutes ago, sup8pdct said:

As i thought, the 7.4 doesn't have the speed corrections the latter ones do. No wounder it didn't work properly.

 

James

Explains why it didn’t work for me then.

[macsonny]

Thanks for the clarification. Just out of interest what’s the difference between a 2764 and 27C64?

[TZJB]

23 minutes ago, macsonny said:

Thanks for the clarification. Just out of interest what’s the difference between a 2764 and 27C64?

A 2764 EPROM can normally be said to be fabricated from NMOS whereas a 27C64 is fabricated from CMOS. CMOS gives the benefit of lower power consumption for the same storage capacity. For instance standby current of the NMOS is around 35 mA whereas CMOS is 0.1 mA. However just use what you can get hold of. You can actually use any PROM up to 27512 as they are all 28 pin, but in this case the data needs to placed at the last 8K of the address range in the programmer software for correct default addressing without adding switches.

[1050]

11 hours ago, macsonny said:

Explains why it didn’t work for me then.

It has some but not all of the 7.7 enhancements.

Comparing files H:\1STXP\!LEE\ATARI\XF551\XF551_C101696 REV 7.7.BIN and H:\1STXP\!LEE\ATARI\XF551\CONVERTED XF551 V7.4.ROM
0000069F: C4 FB
000006A0: C0 A8
000006C0: B8 FF
000006C1: 77 FF
000006C2: F0 FF
000006C3: D3 FF
000006C4: 10 FF
000006C5: 96 FF
000006C6: D3 FF
000006C7: C8 FF
000006C8: F0 FF
000006C9: D3 FF
000006CA: 50 FF
000006CB: 96 FF
000006CC: D3 FF
000006CD: 76 FF
000006CE: D1 FF
000006CF: A4 FF
000006D0: 16 FF
000006D1: 04 FF
000006D2: 1C FF
000006D3: FB FF
000006D4: A8 FF
000006D5: C4 FF
000006D6: A1 FF

 

Your file above, CONVERTED XF551 V7.4.ROM had to have the last half of it replaced with zeros in order to NOT have the above file be a mile long and just no need for that, so I converted to have that last half be zeros instead of FF as all the other XF-551 rom files are done. So there are other parts changed the same as 7.7 but 7.4 wasn't quite good enough it appears.

 

So it would appear that both you down unders with the 50 Hz power grid and PAL machines can use 7.7 Rom

and if so then that answers which is the PAL version - 7.7 with a CRC-32 of D438B4D9.

 

You get the above if you'll use a MS-DOS command called file compare.

fc /b file1 file2>difference.txt

and the difference.txt between the files is above, cut and pasted. /b is the binary switch to avoid text file comparisons and since I'm not keen on the text files or their differences, I use /b. NT windows continues the tradition of MS-DOS commands in their command.com file. It works the same in all windows with NT having much more powerful and feature filled batch file methods than 9x DOS mode could ever dream of.

 

The string of FF in your 7.4 file (on the right side) is where Atari went back into it and made the differences in 7.7 (on the left, file1) to make it work for PAL systems. This 8040 code is filled with lots of "blank" spots of FF which is handy for doing exactly the above with. Thanks for answering the PAL question for me guys.

 

 

[+MrFish]

8 hours ago, 1050 said:

So it would appear that both you down unders with the 50 Hz power grid and PAL machines can use 7.7 Rom

and if so then that answers which is the PAL version - 7.7 with a CRC-32 of D438B4D9.

This is a different hash than the one I posted: Atari XF551 7.7 [NTSC-PAL] {38B97AE3}. There are two different 7.7's - or I've got a bad file?

 

[Edit]

I've verified the hash for the version 7.7 ROM that I posted -- by downloading multiple copies from various threads on the 8-bit forums here, all with the same hash.

So, now, the question is: what 7.7 ROM does this "D438B4D9" hash come from?

 

[phaeron]

There are three differences between 7.4 and 7.7.

 

The first two are the known fixes in the command and data frame receive loops, increasing the bit loop from 28 to 29 machine cycles/bit (1 8040 machine cycle = 15 T-states @ 8.333MHz):

 

 

 

Interestingly, the transmit routine was already at 29 cycles/bit.

 

The third and unexpected change is to the format routine:

 

 

What this change does is check if AUX1=$10 and AUX2=$50, and if so, switches to an alternate mode where the drive keeps formatting the disk in a loop until a failure occurs, at which time it simply exits to the command loop without sending a status code. This looks like a feature that was put in for stress testing in production, and the two bytes spelling out 1050 can't be a coincidence. Tried it out in emulation and verified that it actually does start formatting over and over... need to pull out the XF551 and see if I have 7.4 or 7.7.

 

[sup8pdct]

6 hours ago, 1050 said:

So it would appear that both you down unders with the 50 Hz power grid and PAL machines can use 7.7 Rom

and if so then that answers which is the PAL version - 7.7 with a CRC-32 of D438B4D9.

 

 

The timing fix should work the world over. Bob Puff did his xf551 update rom based on the timings in the 7.4 rom, which didn't work when i got one. Showed him the differences and he quickly updated and sent me a new rom. He has never said anything about different PAL / NTSC versions. This was back in the early 90's....... Man that makes me feel  . . . . . . . old........

 

James

[+Philsan]

Many years ago I solved my XF551 not working with PAL machines with this PAL rom:

https://atariage.com/forums/topic/115775-xf551-pal/

 

Is it the latest PAL rom?

Is there a rom that works with NTSC and PAL machines?

Thanks

 

[sup8pdct]

That should work the world over.

 

 

Here are all versions i believe atari have done for the XF551.

1 and 2 are ntsc only. 3 and 4 should work everywhere.

version 4 has extra code at 9E0 but is rather puzzling as a jump  within the extra code that doesn't seem right  .

 

X09e0:    in    a,p1        ; 09e0 - 09    .
    anl    a,#8        ; 09e1 - 53 08    S.
    jz    X09f0        ; 09e3 - c6 f0    Fp               ??????????????????? jump into
    anl    p2,#0cfh    ; 09e5 - 9a cf    .O
    orl    p2,#10h        ; 09e7 - 8a 10    ..
    anl    p1,#0e7h    ; 09e9 - 99 e7    .g
    jmp    X09b1        ; 09eb - 24 b1    $1
;
    orl    p2,#30h        ; 09ed - 8a 30    .0
    orl    p1,#8        ; 09ef - 89 08    ..             1/2 way in here???????  
    anl    p1,#0efh    ; 09f1 - 99 ef    .o
    jmp    X09b1        ; 09f3 - 24 b1    $1

XF551 7-4-1.rom XF551 7-7 -3.rom XF551 ABCd-4.bin XF551 ntsc-2.bin

Edited July 22, 2022 by sup8pdct
Added versions

[manterola]

One ROM we don't have yet is the XF551 firmware from the intel 8050 (Atari branded version CO70235). I suspect is "original" or "v1.0" version. I have tried with both TL866ii and GQ-4x4 with additional adapter board for MCS-48.

Still I got kind of ramdom F0F0 sequences or sometimes FFFF.

I plan to play with it with the help of my Fujiama friends. 

If you were not aware, Yes, you can use your xf551 without eprom: lift/cut the S3 jumper and add the S4 jumper in the XF551 board and the drive will work with 8050 internal firmware, no need for additional eprom (as long as you have the CO70235)

Any info about dumping this internal firmware will be appreciated. or if you have an old eprom programmer with mcs-48 support.

 

Edited July 22, 2022 by manterola

[1050]

14 hours ago, sup8pdct said:

version 4 has extra code at 9E0 but is rather puzzling

The 9E0 region is the Woolley density switching code, but your copy has been stepped on, last three bytes of line 9E0 are supposed to be FF, FF, FF. And 9F0 continues the altered density switch code.

 

Full details in the comp.sys.8bit link within this link

https://atariage.com/forums/topic/206780-xf551-35-mod/?do=findComment&comment=4226046

 

So it appears to be my bad, the new file discovered a few more pages after the above link is unique, but it is not the PAL version as I thought. Which I foolishly renamed wrong here and lead everyone on a wild goose chase.

We've all had the PAL version all along, apologies to MrFish as his 38B97AE3 is correct in it's file name being for NTSC and PAL machines alike with all changes applied by Atari including the found by phaeron endless format loop with the homage to the 1050 within it. Apologies to Philsan as well, your file is the same as MrFish and the one I always thought was the problem child 38B97AE3. Yes, it is the latest PAL rom and it does work with NTSC too.

 

So my offerings in the other threads are based on the wrong thinking. Here are density switching versions of the proper 38B97AE3 (7.7) roms for the XF-551 drive.

Woolley density switching 7_7 roms.zip

 

 

[+MrFish]

31 minutes ago, 1050 said:

So it appears to be my bad, the new file discovered a few more pages after the above link is unique, but it is not the PAL version as I thought. Which I foolishly renamed wrong here and lead everyone on a wild goose chase.

We've all had the PAL version all along, apologies to MrFish as his 38B97AE3 is correct in it's file name being for NTSC and PAL machines alike with all changes applied by Atari including the found by phaeron endless format loop with the homage to the 1050 within it. Apologies to Philsan as well, your file is the same as MrFish and the one I always thought was the problem child 38B97AE3. Yes, it is the latest PAL rom and it does work with NTSC too.

 

No problem, really, as I was able to download some additional XF551 ROM's that I hadn't looked at before -- in the process. I just wanted to make sure the ROM on my site was a valid 7.7 copy. I thought the Woolley ROM's might have been mixed into this, as they kept coming up in my thread searches too.

 

[Panther]

I've stuck all the XF551 ROMs I've come across here:

http://www.atariverse.com/files/rom/xf551/

 

[phaeron]

To be clear, CRC32 D438B4D9 isn't a PAL-fixed version, it still has the same receive timing as 7.4. This is also XF551 ntsc-2.bin above. Interestingly, it does have the format loop code which lends credence to it being between 7.4 and 7.7. If only we knew whether it was officially 7.5 or 7.6.

 

[Panther]

10 hours ago, phaeron said:

To be clear, CRC32 D438B4D9 isn't a PAL-fixed version, it still has the same receive timing as 7.4. This is also XF551 ntsc-2.bin above. Interestingly, it does have the format loop code which lends credence to it being between 7.4 and 7.7. If only we knew whether it was officially 7.5 or 7.6.

 

Thus, it's listed on my site as "XF551 360K 7.x NTSC {D438B4D9}.rom".  Perhaps the community should designate it as 7.5 or 7.6 so it can fall in place.  I opt for 7.5 since it's really just that format loop that's different.

 

[phaeron]

6 minutes ago, Panther said:

Thus, it's listed on my site as "XF551 360K 7.x NTSC {D438B4D9}.rom".  Perhaps the community should designate it as 7.5 or 7.6 so it can fall in place.  I opt for 7.5 since it's really just that format loop that's different.

Problem is, we don't know if it's 7.5 or 7.6 without a picture of the EPROM with the version on it. For all we know, it might just be a non-official modified ROM, which has already happened a couple of times in the linked threads.

 

[Panther]

On 7/20/2022 at 12:39 AM, MrFish said:

Atari XF551 Turbo {3852A8D4}

Does anyone know what this ROM is?  It's quite different from the others.