Re: REV 3 - The beginning
Posted: Wed Apr 07, 2021 10:41 pm
Nice!
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REV 3 - REV 5 - The beginning (ST536)
https://www.exxosforum.co.uk/forum/viewtopic.php?f=94&t=3992
Page 25 of 71
Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 7:46 am
Great work @exxos
Nice!
Nice!
Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 9:44 am
Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 11:44 am
It looks like something really starts to struggle over 61Mhz. I have disabled the SDRAM as well.. I think it could just be the bus isolators.. I mean they take 20ns to disable... along with the ROM it is mostly moaning the ROM is having problems being accessed, and I have slowed its access right down as well. I put the plastic package one in which otherwise is working fine at 50 MHz, that one does not even boot up, so I assume it is the CPU actually tripping up and nothing else.
I am going to put a faster buffer on the next revision of the board. It is hard to find one that JLC stock , which are actually faster as well.
I am going to put a faster buffer on the next revision of the board. It is hard to find one that JLC stock , which are actually faster as well.
Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 1:01 pm
Yeah i never got 030s past 56-57Mhz without parts of them stopping to work. Think there is a fundamental limit somewhere there.
S
S
Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 1:07 pm
In terms of long-term stability 50Mhz seems to be about as high as you could really go anyway. I have ordered a couple of supposed different mask EC's to see if they are any different.terriblefire wrote: ↑Thu Apr 08, 2021 1:01 pm Yeah i never got 030s past 56-57Mhz without parts of them stopping to work. Think there is a fundamental limit somewhere there.
Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 5:02 pm
Been busy rerouting the buffer isolator chips... It went from two chips to one chip, the fastest one I can really find is a ABT version. About 7ns isolation time, the old ones were about 20ns.
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Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 7:43 pm
Feking Eagle libs 
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Re: REV 3 - The beginning
Posted: Thu Apr 08, 2021 9:31 pm
Some time later... hope it fits this time...
EDIT:
Yep!
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EDIT:
Yep!
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Re: REV 3 - The beginning
Posted: Fri Apr 09, 2021 11:43 am
The board was running most of yesterday at 50MHz on my H4...
The results I was keeping a eye on.. The GEM dialog box ( actually that should probably be spelt dialogue ?
) It was interesting because in the morning the test was 300%.. And during the day when it all heated up in my room picked actually dropped to 299%.. And around midnight when it had dropped in temperature it went back up to 300% again! just goes to show how very small tolerances in hardware can affect things.
- IMG_6402.JPG (216.88 KiB) Viewed 2253 times
The results I was keeping a eye on.. The GEM dialog box ( actually that should probably be spelt dialogue ?
) It was interesting because in the morning the test was 300%.. And during the day when it all heated up in my room picked actually dropped to 299%.. And around midnight when it had dropped in temperature it went back up to 300% again! just goes to show how very small tolerances in hardware can affect things.- IMG_6403.JPG (283.54 KiB) Viewed 2253 times