TT issues. Help welcome...

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Anzac
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Re: TT issues. Help welcome...

Post by Anzac » Thu Aug 31, 2017 4:14 pm

yeah, i can do that... i could also try the floppy drives on the MSTE, but alas, don´t have a VGA adapter.. :(
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Atari 2600 Jr - Atari Mega ST - Atari Mega STe - Atari TT - Atari Falcon - SH205 - Megafile 20

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exxos
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Re: TT issues. Help welcome...

Post by exxos » Thu Aug 31, 2017 4:44 pm

Anzac wrote:
Thu Aug 31, 2017 4:14 pm
yeah, i can do that... i could also try the floppy drives on the MSTE, but alas, don´t have a VGA adapter.. :(
:(

Of course the floppy drive & hard drive in the MSTE are working, so do they both work on the TT ? (sorry if you say this before already, just getting a bit confusing what you tried in where).
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

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rpineau
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Re: TT issues. Help welcome...

Post by rpineau » Thu Aug 31, 2017 5:03 pm

On the TT the SCSI drive doesn't go through the ST DAM but use another DMA controller. The ST DMA is used for the floppy and the ST DMA port on the back of the TT. The SCSI controller (Z85C30) is driver by the DMAC and DCU component (U900 and U901). So the fact that the SCSI workd doesn't mean there isn't a problem with the ST DMA and.or FDC.
Based on your test, it could be what exxos talks about regarding the DMA and pull-uo. It could also be an issue with the FDC (WD1772) or the 74LS06 that is between the FDC and the floppy connectors.
if you have a DMA hard drive you could test it on the TT which would test the DMA itself independently from the FDC.
As you have a know working floppy drive from the MSTE we know it's between the DMA, FDC or 74LS06 si we should be able to test these.

Regarding the TT Ram that definitely sounds like a defective SIMM.
I used these on mine : 4MB 60ns 3-chip Parity 30-pin FPM SIMM (p/n AAK) from this page : http://www.memoryx.com/generic-memory-30-pin-simm.html
IF you can find some non-parity one they would work too as the parity bit is not used on the Atari TT-Ram card as far as I can remember.

Rodolphe

Anzac
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Re: TT issues. Help welcome...

Post by Anzac » Thu Aug 31, 2017 5:12 pm

exxos wrote:
Thu Aug 31, 2017 4:44 pm
Anzac wrote:
Thu Aug 31, 2017 4:14 pm
yeah, i can do that... i could also try the floppy drives on the MSTE, but alas, don´t have a VGA adapter.. :(
:(

Of course the floppy drive & hard drive in the MSTE are working, so do they both work on the TT ? (sorry if you say this before already, just getting a bit confusing what you tried in where).
no worries Chris, it´s up to me to try and as clear as possible.

resuming:
original 9.1GB SCSI HDD was not working. replaced with 50MB SCSI HDD from external HDD (AHS-52 from FSE - non-original Atari external HDD with two 50MB drives). 50MB drive working ok. initial issues with 50MB due to incompatible software on AUTO folder. no hard drive issues since.

original Epson SMD-380 was working ok until that 4 hour session working the floppy non-stop.
replacement Sony MFP-920 floppies give same error message.
MSTE floppy identical.
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Atari 2600 Jr - Atari Mega ST - Atari Mega STe - Atari TT - Atari Falcon - SH205 - Megafile 20

Anzac
Posts: 54
Joined: Thu Aug 24, 2017 6:50 pm
Location: Portugal

Re: TT issues. Help welcome...

Post by Anzac » Thu Aug 31, 2017 5:18 pm

rpineau wrote:
Thu Aug 31, 2017 5:03 pm
On the TT the SCSI drive doesn't go through the ST DAM but use another DMA controller. The ST DMA is used for the floppy and the ST DMA port on the back of the TT. The SCSI controller (Z85C30) is driver by the DMAC and DCU component (U900 and U901). So the fact that the SCSI workd doesn't mean there isn't a problem with the ST DMA and.or FDC.
Based on your test, it could be what exxos talks about regarding the DMA and pull-uo. It could also be an issue with the FDC (WD1772) or the 74LS06 that is between the FDC and the floppy connectors.
if you have a DMA hard drive you could test it on the TT which would test the DMA itself independently from the FDC.
As you have a know working floppy drive from the MSTE we know it's between the DMA, FDC or 74LS06 si we should be able to test these.

Regarding the TT Ram that definitely sounds like a defective SIMM.
I used these on mine : 4MB 60ns 3-chip Parity 30-pin FPM SIMM (p/n AAK) from this page : http://www.memoryx.com/generic-memory-30-pin-simm.html
IF you can find some non-parity one they would work too as the parity bit is not used on the Atari TT-Ram card as far as I can remember.

Rodolphe
Hi Rodolphe, thanks for pitching in. i do have an SH205 and the AHS-52 that i could try and connect to the ACSI port. not sure if i have cables, but i´ll check later.

thanks.
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Atari 2600 Jr - Atari Mega ST - Atari Mega STe - Atari TT - Atari Falcon - SH205 - Megafile 20

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exxos
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Re: TT issues. Help welcome...

Post by exxos » Thu Aug 31, 2017 5:37 pm

Anzac wrote:
Thu Aug 31, 2017 5:12 pm

no worries Chris, it´s up to me to try and as clear as possible.

resuming:
original 9.1GB SCSI HDD was not working. replaced with 50MB SCSI HDD from external HDD (AHS-52 from FSE - non-original Atari external HDD with two 50MB drives). 50MB drive working ok. initial issues with 50MB due to incompatible software on AUTO folder. no hard drive issues since.

original Epson SMD-380 was working ok until that 4 hour session working the floppy non-stop.
replacement Sony MFP-920 floppies give same error message.
MSTE floppy identical.

So if you boot to GEM, and try to format a floppy, what happens ?
4MB STFM 1.44 FD- VELOCE+ 020 STE - 4MB STE 32MHz - STFM 16MHz - STM - MEGA ST - Falcon 030 CT60 - Atari 2600 - Atari 7800 - Gigafile - SD Floppy Emulator - PeST - HxC - CosmosEx - Ultrasatan - various clutter

https://www.exxoshost.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxoshost.co.uk/atari/last/storenew/ - All my hardware mods for sale - Please help support by making a purchase.

Anzac
Posts: 54
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Location: Portugal

Re: TT issues. Help welcome...

Post by Anzac » Thu Aug 31, 2017 6:10 pm

i will post screenshots later. otherwise i´m just giving information based on my memory where an error message could be related to original Atari drives or the Sony.
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Atari 2600 Jr - Atari Mega ST - Atari Mega STe - Atari TT - Atari Falcon - SH205 - Megafile 20

Atarian Computing
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Re: TT issues. Help welcome...

Post by Atarian Computing » Thu Aug 31, 2017 7:33 pm

I wrote this in a PM to Anzac but will post here if it helps others.

I have 2 extra TT-Ram boards like the one you have. One with the maximum 16MB RAM (4x4MB). I know it works for a fact. Let me know if you want to try it.

Many times the TT-RAM connector gets oxidized and there are contact problems resulting in problems. Only solution is to replace the connector on the motherboard.

Anzac
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Location: Portugal

Re: TT issues. Help welcome...

Post by Anzac » Thu Aug 31, 2017 8:03 pm

It´s a really nice offer. i will try the MSTE sticks first. if errors persist then it´s either the board or the mainboard conector.

also, i can also offer spare original batteries for MSTE/TT RTC, if anyone needs.
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Atari 2600 Jr - Atari Mega ST - Atari Mega STe - Atari TT - Atari Falcon - SH205 - Megafile 20

Anzac
Posts: 54
Joined: Thu Aug 24, 2017 6:50 pm
Location: Portugal

Re: TT issues. Help welcome...

Post by Anzac » Fri Sep 01, 2017 4:23 pm

ok. so last night i went home, opened the MSTE, removed the WD1772 and floppy cable, installed on the TT and tried again.

results were the same with either the MSTE floppy or the sony MFP-920:
Floppy_error.JPG
Floppy_error.JPG (75.96 KiB) Viewed 663 times
out of desperation also removed an old Chinon D357 from a MegaST and tried it. same.

also removed the MSTE SIMMs but with no working drive, no way to test if it´s the RAM board or the SIMMs...

also found an ACSI cable and have to try both the Megafile 20 and the SH205, but they are in unknown condition and i would have to clear some desk space, so it will have to be another time.

running out of ideas... :cry:
____________________________________________________________________________________
Atari 2600 Jr - Atari Mega ST - Atari Mega STe - Atari TT - Atari Falcon - SH205 - Megafile 20

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