1541 Drive rom dumper

[MrMartian]

Does anyone have a working program to dump the ROM of a 1541 via the 64? I have a ROM that I'm trying to be delicate with and would like a dump of it... (and perhaps the world...)

 

Thanks!

[carlsson]

Would it be a custom 1541? You have a bunch of firmwares already dumped, but of course yours might differ.

 

Here is a fairly recent dumper by a seasoned coder: https://csdb.dk/release/?id=49683

[MrMartian]

37 minutes ago, carlsson said:

Would it be a custom 1541? You have a bunch of firmwares already dumped, but of course yours might differ.

 

Here is a fairly recent dumper by a seasoned coder: https://csdb.dk/release/?id=49683

Well, from a quick reading, I feel mine differs.. ? -04 is suspected to not exist...

 

I've tried that dumper, and either it takes >4 hours to dump or something isn't working...

[carlsson]

Aha. Yes, it is listed as recalled by Commodore. Regarding the dumper, I've never tried it but I agree that it shouldn't take four hours to dump 8 kilobytes.

 

If you have some X*1541 series cable, ZoomFloppy or other compatible device, you might be able to use OpenCBM to dump a ROM:

cbmctrl download 8 0xc000 0x4000 > 1541.rom

 

https://opencbm.trikaliotis.net/opencbm-17.html

[MrMartian]

1 hour ago, carlsson said:

Aha. Yes, it is listed as recalled by Commodore. Regarding the dumper, I've never tried it but I agree that it shouldn't take four hours to dump 8 kilobytes.

 

Realled eh? I find it interesting that there seems to be no dumps of it anywhere.. It will be interesting to see what bugs there are in it that made it so bad?

[carlsson]

Here are some of the references I found last night:

 

Quote

William Levak wrote:

901229-02 and previous versions use a header gap of 8 bytes. 901229-03 and later versions use a header gap of 9 bytes. This is the only difference between 901229-02 and 901229-03.

 

901229-04 is unknown. 901229-05 changes some of the serial bus routines, and NOPs out the auto start routine. 901229-04 could potentially make only some of these changes, if it exists.

901229-06 adds a patch that sets location $51 (current track) to $FF before formatting a disk. This is apparently to recover from a prior failed format attempt. This is the only difference between 901229-05 and 901229-06.

901229-07 is known only from the parts list of the 1541B/C. It is probably the same as the upper half of 251968-01.

 

 

Quote

Julian Perry wrote:

I have never seen a 901229-04 ROM . I came to the conclusion that it must have been an internal revision, never released.

 

Quote

Bob Skyles & Bryce Nesbitt wrote in the 1541 Flash! instruction manual from 1984:

8. The Operating ROM should have one of the following numbers on it: 901229-01, 901229-03, 901229-05 901229-04 (recalled by Commodore)

 

It is true that a dump of the -04 has been requested for more than 10 years, so if your EPROM is genuine (i.e. the label doesn't lie), I understand if you want to dump it.

Edited July 28, 2020 by carlsson

[carlsson]

Also I remember that the 2564 is an uncommon EPROM type that very few programmers can handle so it wouldn't help if you lifted the chip off the board to read it unless you have a very advanced EPROM programmer. On the plus side is that it should be pin compatible with a 2364 ROM without the need of an adapter as otherwise seen with using the far more common 2764.

[+OLD CS1]

I am pretty sure some folks in the TI sub can dump a 2564 if it refuses to dump in situ.

[MrMartian]

Ah well, I was trying to dump it without pulling it from the board. No such luck it seems. As for dumping it once out of the board, a quick arduino program made that easy..

901229-04.bin

[wierd_w]

This needs to be added to the various collections out there for completeness, and analysis.

[MrMartian]

6 minutes ago, wierd_w said:

This needs to be added to the various collections out there for completeness, and analysis.

I agree... I know there are other more Commodore specific forums out there, but I'm a member here and not there.. I'm sure it will get around.

 

I do find it interesting that this is on an EPROM in this SX64. I guess it never made it far enough to make it worthwhile to be a mask rom? Then again, the actual ROM on the main board is also an EPROM and not a mask. Early production SX?

[+OLD CS1]

3 hours ago, MrMartian said:

I do find it interesting that this is on an EPROM in this SX64.

I knew I recognized that board.  Now I am curious if any of my SXes have this ROM version.

[carlsson]

I'm not sure how the /incoming FTP folder works, but otherwise you can send it by email to bo [AT] zimmers.net with some info what it is and how you found it.