AtariFox STFM service blog

[AtariFox]

To be honest I haven't had a reason to check the megafile yet, as the ST itself has issues. I'll check out that capacitor.

The big 4700 one? Could the ASCI socket be bad?


Also a little history of the machine, is that it was used constantly for many years by a DJ/midi music maker.

[Steve]

To be honest I haven't had a reason to check the megafile yet, as the ST itself has issues. I'll check out that capacitor.

The big 4700 one? Could the ASCI socket be bad?


Also a little history of the machine, is that it was used constantly for many years by a DJ/midi music maker.

I'm not going to look at the ASCI till the floppy issue is solved, by capacitor I meant c68 you were talking about.

[AtariFox]

The big 4700 one? Could the ASCI socket be bad?


Also a little history of the machine, is that it was used constantly for many years by a DJ/midi music maker.

I'm not going to look at the ASCI till the floppy issue is solved, by capacitor I meant c68 you were talking about.

Alright, thank you. Sorry for all the questions. I'm still quite new to Atari side of things especially the diagnosing and way things work. I'm more Commodore 64.

I'm not sure why it's giving you the error when you've done more than i did and it was working before i messed with soldering. Thank you for your continued persistence.

[Steve]

Hmm, I'm at the point where I may need some ideas from others on the forum.
I recently
- removed marpet ram
- reflowed most major chips and component
- reflowed floppy header on board

* I can successfully format a floppy, so I would assume that means writing is OK
* But still cannot successfully read programs, directory contents is OK, just throws up damaged error upon loading a PRG

[exxos]

Use FCOPYII and let that run , you can tell better if its stalling on any particular tracks.. you can also increase to 10 sectors to make it a tougher test.

[Steve]

Use FCOPYII and let that run , you can tell better if its stalling on any particular tracks.. you can also increase to 10 sectors to make it a tougher test.

One small anomaly I just noticed is this: On the STFM KIT DUAL TOS kit that is installed (with ube chip) The ube has not been connected to pin 16 of CPU, the bank select jumper is on bk2, but TS is bridged! Which according to your instructions, could mean the ube chip is damaged. I know this probably has nothing to do with the floppy. But I might unsolder the TS blob, and test the other TOS bank.

[exxos]

One small anomaly I just noticed is this: On the STFM KIT DUAL TOS kit that is installed (with ube chip) The ube has not been connected to pin 16 of CPU, the bank select jumper is on bk2, but TS is bridged! Which according to your instructions, could mean the ube chip is damaged. I know this probably has nothing to do with the floppy. But I might unsolder the TS blob, and test the other TOS bank.

TS jumper is used to connect the UBE chip to the ROM A17 (bank select) so you remove the jumper link connector.. if both are fitted, then your shorting out the UBE output with the jumper link connector... I don't know how UBE chip will react without reset connected either.. you could be randomly switching between TOS versions causing in effect ROM corruption.

EDIT:
TS pad is connected to the middle jumper pin.. probably make more sense to understand...

[DoG]

Reset on 68000 is on pin 18, not pin 16. Just a heads up.

[Steve]

Okay I added a DMA sip 10k resistor pullup and it's a little better. Managed to load yaart off floppy. Will do more testing tomorrow.

[AtariFox]

Use FCOPYII and let that run , you can tell better if its stalling on any particular tracks.. you can also increase to 10 sectors to make it a tougher test.

One small anomaly I just noticed is this: On the STFM KIT DUAL TOS kit that is installed (with ube chip) The ube has not been connected to pin 16 of CPU, the bank select jumper is on bk2, but TS is bridged! Which according to your instructions, could mean the ube chip is damaged. I know this probably has nothing to do with the floppy. But I might unsolder the TS blob, and test the other TOS bank.

Hi there. I bought that ToS upgrade from Exxos store, because there was no 1.04 chips, It's a dual TOS chip. I did not need anything to do with the UBE.
I'd rather the dual tos not get fuddled with in case i want to remove it at at a later date. The jumper if i remember right is to select TOS version to load. Bank 1 is 1.02 and Bank 2 is 1.04.

The UBE chip isnt used nor connected.

It reads ToS 1.04 and has done since i first got the upgrade, i' have not needed to mess with it as i just want it to run 1.04 and i just switch the jumper if i want tos 1.02.

Okay I added a DMA sip 10k resistor pullup and it's a little better. Managed to load yaart off floppy. Will do more testing tomorrow.

So you think i must have done something to the DMA chip? I can't believe I caused so much of an issue with just the soldering thing i messed up with.

I must have really buggered up something for it to need all this.