exxos's Atari, Amiga & retro forum

Calab wrote: 08 Oct 2021 16:25 Resistor pack on the DMA chip made things worse. I will be removing it.

That is not really a good idea unless you shorted something out or used the wrong value or fitted incorrectly etc. The resistor fix has been present for a number of years on likely 100s of machines now without problem.

exxos wrote: 08 Oct 2021 16:45 That is not really a good idea unless you shorted something out or used the wrong value or fitted incorrectly etc. The resistor fix has been present for a number of years on likely 100s of machines now without problem.

Ya... I'm an idiot.

I ordered the 2.2K instead of the 10K pack from your website. I'll be swapping that out later today. :oops:

Been away from the ST for a bit, but still having issues with the ACSI port on my Mega ST2 machine...

At this point I have the CORRECT resistor pack mounted to my DMA chip. I have not replaced any data or address bus resistor packs... I'm currently trying to find a how-to for this particular machine so I identify the correct parts.

I have used the UltraSatan (ID1 and ID2) on an ST with 1.02 TOS and an STE (I don't remember the TOS version) and the unit did work better - but still had issues with some of my SD cards. I've separated the troublesome SD cards from my batch to keep the confusion to a minimum.

Just now I used the PP hard disk driver to partition and initialize a good 8GB SanDisk card with a number of "C16" 512MB partitions. I'm using TOS 1.04, so this size should be acceptable. I can put the SD card into a PC and copy files to these partitions. If I boot the SD card in my ST it sees all the partitions and I can see the files that I put onto the card using my PC. If I try to copy anything to that SD card in my ST, it seems to work, but then there are no files displayed for that drive. If I reboot, I can see the content of the drive again, but none of the files I tried to copy are there - EXCEPT for the first file, but it is 0 bytes long.

Another related issue is that I have a MegaFile60 using ID3. If I connect it instead of my UltraSatan the ST find the device ID3, but says it's unknown.

So... at this point, is changing the data/address bus resistor packs going to help? Is there a FAQ for this process in a Mega ST2? (Should https://www.exxosforum.co.uk/forum/viewt ... 235#p40318 work for a Mega ST2?)

{edit}
Just for the sake of completeness...

- My Mega ST2 is running with a new Meanwell PSU.
- I have tried three different power adapters on the UltraSatan with no change in operation.

Calab wrote: 08 Oct 2021 16:27
I haven't had issues with these SD cards on my Windows machine, nor on my TRS-80 Color Computer with SDC, but the US might just be more sensitive.

Just because SD cards work in one machine there is no guarantee they will work in another I'm afraid. I use only branded cards, and in most scenarios find that basic SD cards, so nothing high speed, will give you the best results.

That's why I tend to buy batches of the blue Sandisk cards that are the really basic ones. I have had no reliability issues with them across multiple platforms, so my CosmosEx, my US my SIDE3 for Atari 8Bit, my Erebus for Oric Atmos, my ZX81 ZXExpand+ and last but by no means least my vDrive QL.

If you haven't done the databus resistor packs it should be on your to-do list for sure.