Re: Mega STe stability issues.
Posted: 27 Apr 2022 15:21
Give this a try https://www.exxosforum.co.uk/forum/viewt ... =17&t=1484
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Not really modifications, it's just soldering wires on some pins to connect back to the card, no cut tracks or anything like that, in theory removing the card just means I have a wire harness with 5 pins not connected to anything.troed wrote: 27 Apr 2022 18:30 Did you make any modifications to the MSTE when you first installed the MonSTEr perhaps? ("To get the blitter working") I think.
http://www.fairlite.co.uk/AtariKit/mons ... olders.txt
So I measured the voltage on the pins of the ISA connector.scsilord wrote: 26 Apr 2022 08:40 The ATI cards (mach32/64) are very power hungry and can cause voltage drops. I had some stability issues with a mach32 until I soldered a +5V and GND connector on the nova ISA connector board. Delivered voltage went in my case from 4.5 to 5.05.
ACSI/DMA is always a trouble maker. Shorten the ribbon cable you got from lotharek as much as possible, just make sure you can still open your drive bay to access your ultrasatan.
The +5 volts is fine. The +5 volts have to go over the mainboard and the ribbon cable to the VME backplane and through the Nova adapter and over 30cm long ribbon cables to the ISA slot. The +5 volts drop a bit, which is okay and quite normal. It's not a problem either.Dbug wrote: 28 Apr 2022 17:57So I measured the voltage on the pins of the ISA connector.scsilord wrote: 26 Apr 2022 08:40 The ATI cards (mach32/64) are very power hungry and can cause voltage drops. I had some stability issues with a mach32 until I soldered a +5V and GND connector on the nova ISA connector board. Delivered voltage went in my case from 4.5 to 5.05.
ACSI/DMA is always a trouble maker. Shorten the ribbon cable you got from lotharek as much as possible, just make sure you can still open your drive bay to access your ultrasatan.
I have +4.89v, -12.65v and +12.09v respectively for the +5, 12 and +12, and nothing at all on the -5v (which I believe is only required for some very rare cards so should be ok?)
Do these voltage seem ok?
Thanks!frank.lukas wrote: 28 Apr 2022 18:40 The +5 volts is fine. The +5 volts have to go over the mainboard and the ribbon cable to the VME backplane and through the Nova adapter and over 30cm long ribbon cables to the ISA slot. The +5 volts drop a bit, which is okay and quite normal. It's not a problem either.