Exxos I am using original Atari drives on this machine, but do you think https://www.exxosforum.co.uk/forum/viewt ... =17&t=1395
is worth it? the pullups on the buffer?
James
MegaST - something recient.
Re: MegaST - something recient.
If it's in the mandatory fixes then it's not optional.
If you have a spare DMA, try it ?
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
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rubber_jonnie
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Re: MegaST - something recient.
Ok, so the DMA is the one next to the FDD controller, and since it's in a socket, you could try just swapping it out.
You may want to have a look here too: https://www.exxosforum.co.uk/forum/viewt ... hilit=mega
Ignore the memory issues, for me it was the DMA that was bad.
Also, since the DMA is already in a socket (They are normally soldered in), I'd use the schematic to trace all the endpoints from the socket on the back of the board to their next endpoints and make sure that they have continuity.
Mega boards don't fare well with rework like socket installs, so you may have bad connections that can be fixed with a bodge wire. I had to do that on one of mine.
You may want to have a look here too: https://www.exxosforum.co.uk/forum/viewt ... hilit=mega
Ignore the memory issues, for me it was the DMA that was bad.
Also, since the DMA is already in a socket (They are normally soldered in), I'd use the schematic to trace all the endpoints from the socket on the back of the board to their next endpoints and make sure that they have continuity.
Mega boards don't fare well with rework like socket installs, so you may have bad connections that can be fixed with a bodge wire. I had to do that on one of mine.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
Re: MegaST - something recient.
OH, ok, but you specifically say in that thread its for the 920 drive.. I will do it.. I am assuming it cant hurt if I am using original drives.
James
Re: MegaST - something recient.
So... I guess I can only say that in the case of this board.. the manditory fixes.. WERE NEEDED!!
I have been testing the board for 3 days now.. it's good. Final pics.
I have been testing the board for 3 days now.. it's good. Final pics.
- 20211124_135835.jpg (323.84 KiB) Viewed 1499 times
- 20211124_135922.jpg (590.3 KiB) Viewed 1499 times
Re: MegaST - something recient.
So this solved your strange floppy problems ?
https://www.exxosforum.co.uk/atari/ All my hardware guides - mods - games - STOS
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
https://www.exxosforum.co.uk/atari/store2/ - All my hardware mods for sale - Please help support by making a purchase.
viewtopic.php?f=17&t=1585 Have you done the Mandatory Fixes ?
Just because a lot of people agree on something, doesn't make it a fact. ~exxos ~
People should find solutions to problems, not find problems with solutions.
Re: MegaST - something recient.
All I can say for sure, is once the pullups were done, and I changed the on board C4 7400uf cap, after the first 2 days.. where I was still got some crashing.. I have now run that board with games, and gembench and memtest etc..etc.. and I have not been able to crash it.
The resistors on the 7406 I did today.. they did not make a difference???? but everything is still working.. so all good.
knock on wood I am considering this board working!!
James
The resistors on the 7406 I did today.. they did not make a difference???? but everything is still working.. so all good.
knock on wood I am considering this board working!!
James