exxos's Atari, Amiga & retro forum

Hi all,

I recently buy a Atari 1040STf with megafile 30, the Atari is not working (white screen).
I have start the computer with diagnostic cartridge and I have a error i6 and t0.
Can somebody guide me to find where come the problem ?
Regards.

I'd suspect either a faulty GLUE chip or bad contacts in the socket. Have you tried removing the GLUE and cleaning the contacts?

rubber_jonnie wrote: 18 Sep 2021 09:18 I'd suspect either a faulty GLUE chip or bad contacts in the socket. Have you tried removing the GLUE and cleaning the contacts?

Hi rubber_jonnie,

Thanks for the fast reply, I haven't pull out the glue, I don't have the tool to remove.
I have only put flux cleaner, I will try to remove on Monday and post the result.

Regards.

Cyril

Atome_X wrote: 18 Sep 2021 09:30

rubber_jonnie wrote: 18 Sep 2021 09:18 I'd suspect either a faulty GLUE chip or bad contacts in the socket. Have you tried removing the GLUE and cleaning the contacts?

Hi rubber_jonnie,

Thanks for the fast reply, I haven't pull out the glue, I don't have the tool to remove.
I have only put flux cleaner, I will try to remove on Monday and post the result.

Regards.

Cyril

Yes, best to get a tool to remove the GLUE. Try tweaking the contacts too: https://www.exxosforum.co.uk/forum/view ... hilit=Plcc

Good morning,

I find the tool to remove the GLUE and MMU, I have clean both and move the contact like you tell me, but unfortunately it's the same I use the test cartridge V3.61 and also the ST Test V4.4.
With the V4.4 have no I6 error but all the time t0 map error.
Have all the tools to check if you have a idea ?
Regards.

@Atome_X use the 4.4 diagnostic cart its the better one to use for an STF.

T0 is related to an MFP timer fault. I think I'd check the soldering on the MFP and try another MFP if you have one.

Atome_X wrote: 20 Sep 2021 10:46 Good morning,

I find the tool to remove the GLUE and MMU, I have clean both and move the contact like you tell me, but unfortunately it's the same I use the test cartridge V3.61 and also the ST Test V4.4.
With the V4.4 have no I6 error but all the time t0 map error.
Have all the tools to check if you have a idea ?
Regards.

I probably should have asked earlier, but have you checked the PSU voltages are all good? Only 5v is necessary to boot to desktop BTW.

Just checking, but you are trying to boot with the Megafile disconnected at this point? It's always best to try and boot with a minimal config to minimise what you're investigating.

Also, I presume you are waiting some time to allow the desktop to appear, I've seen it take a couple of minutes before.

So, looking back at your pics, and there is a bit of a clue. T0 MFP Timer. I expect that relates to one of the many timers the 68901 has.

This suggests you have a problem with the 68901, so you probably want to download the datasheet and start checking what's going on.

I'd start by checking the chip has good power, and seeing what state the reset pin is in. It should be 5v when running and 0v when reset is pressed.

I'd also take a look at the schematic and buzz out all of the connections to the 68901 to ensure there are no bad connections from it to the mainboard, and also visually check to see if there is any damage to any of the traces going to/from the 68901.

Not knowing what other test kit you have, or if you have a second working machine to compare to, it's hard to make more suggestions.

Unfortunately the 68901 is likely to be soldered in and can be difficult to remove due to quite large ground planes.

PhilC wrote: 20 Sep 2021 10:56 @Atome_X use the 4.4 diagnostic cart its the better one to use for an STF.

T0 is related to an MFP timer fault. I think I'd check the soldering on the MFP and try another MFP if you have one.

Hi PhilC,

I have try some test with serial cable, but there is no signal out from the MFP pin to rs232, I think the MFP is dead.
I have order one in Exxos store with rainbow TOS.
When l will receive, I will post the result here.
Thanks to all

Does the MFP (68901) have a working crystal? Should be 2,4576MHz

DoG wrote: 20 Sep 2021 15:38 Does the MFP (68901) have a working crystal? Should be 2,4576MHz

Yes 2,4576mhz on xtal1,2 and 4Mhz on clk.