exxos's Atari, Amiga & retro forum

Hi,

Its taken ages to get around it but finally did my 536,.. but back screen :-) and no boot.

CPLD programs ok, programmed latest version.
5V test points are ok when inserted in 68k socket

Tried in A2000 (rev 6.2) and A500++, same result. Both boards work fine with the 68000 in place.

Looking at some previous threads no1 cause is poor soldering on the tight pitch stuff,.. i've checked it loads of times, but will upload some close ups.

Anything else i should check ?, i dont have a scope at home but could get one from work.

amimjf wrote: 11 Sep 2020 16:53 Anything else i should check ?, i dont have a scope at home but could get one from work.

Are you trying to boot Kickstart or DiagROM.. first goal is boot DiagROM.

Booting kickstart, i have a DiagROM from the A500++ build, will try that.

Images included.

If there is nothing at all, I'd check/swap the oscillator. That soldering all looks fairly nice.

PaulJ_2.0 wrote: 11 Sep 2020 17:11 If there is nothing at all, I'd check/swap the oscillator. That soldering all looks fairly nice.

Yes i looked at that oscillator and thought... i wonder if thats a crystal and not an oscillator.. i've made that mistake before and it looked like that.

Black screen with DiagROM as well.

Clock is a "SIT8008BC"... "100MHz XO (Standard) HCMOS, LVCMOS Oscillator 3.3V Enable/Disable 4-SMD, No Lead" ough no !,.. have i been really dumb ?

That's a programmable oscillator?


Edit:
Oh it's ok, I just checked the SiT8008BC part number and it took me to a datasheet of a programmable 8-110mhz osc.

Datasheet says "Low Power Programmable Oscillator"....

But the exact part i ordered is "SIT8008BC-83-33E-100.000000T", the so 100.00000 should be the frequency,.. i guess a need to scope it.

100mhz is a bit quick for the scopes have i think, is there a place where its divided down i could check ?

amimjf wrote: 11 Sep 2020 17:36 Datasheet says "Low Power Programmable Oscillator"....

But the exact part i ordered is "SIT8008BC-83-33E-100.000000T", the so 100.00000 should be the frequency,.. i guess a need to scope it.

Yes that part is not correct. Thats a programmable osc. You need a plain 100Mhz osc.

amimjf wrote: 11 Sep 2020 17:36 100mhz is a bit quick for the scopes have i think, is there a place where its divided down i could check ?

The CPU clock at the 030.. grab OpenBoardView and the files from the terriblefire-binaries area... but i think that part is not correct at all I suspect that osc is outputting 2Hz when it boots.