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Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: spaceman88 on November 23, 2008, 01:05:03 AM

Title: A4000 CPU cards
Post by: spaceman88 on November 23, 2008, 01:05:03 AM

In order to troubleshoot some A4000's, can I swap 68030 & 68040 boards or do I need to change jumpers or something?

Thanks

Title: Re: A4000 CPU cards
Post by: Macabre on November 23, 2008, 01:17:53 AM

Hi,

You need to set some jumpers.
Plz take a look at http://www.zimmers.net/cbmpics/cbm/amiga/a4000jumpers.html
Dont remember if you have to set J100 and J104 or only J100.

There about under the processor card and next to each other

Title: Re: A4000 CPU cards
Post by: Plaz on November 23, 2008, 01:30:26 AM

You do need to set both jumpers to match the type of card you have installed. These jumpers sit side by side near the middle of the motherboard on the right side of the daughter card connector.

J100: CLK90 Clock Source
1-2 Closed:(Internal CLK for 68020/68030)
2-3 Closed (External CLK for 68040)

J104: CPU Clock Source
1-2 Closed: Internal
2-3 Closed (External CLK for 68040)

Plaz

Title: Re: A4000 CPU cards
Post by: spaceman88 on November 23, 2008, 01:31:30 PM

Hi,
Thanks for the info. I just found out that one of the A4000's is a A4000T (don't know if it's a Commodore or Escom yet) is the setup the same?

Thanks

Title: Re: A4000 CPU cards
Post by: Kin-Hell on November 25, 2008, 01:24:21 PM

Quote

spaceman88 wrote:
Hi,
Thanks for the info. I just found out that one of the A4000's is a A4000T (don't know if it's a Commodore or Escom yet) is the setup the same?

Thanks

Yes, A4000T has INT & EXT jumpers & are also maked J100 & J104. C=A4KT or Escom A4KT are the same.

In a nutshell:

Set both to INT when using any accelerator that uses the Amiga Mobos timing Crystal.
Set to EXT when using any accelerator that uses its own Timing crystal.

:-)

Title: Re: A4000 CPU cards
Post by: Sandman on November 25, 2008, 04:33:19 PM

When I installed my WarpEngine I am pretty sure I set both of the jumpers to external but I can't remember now.

Is there any way to tell without opening up the case?

Sysinfo reports 68040@40 so does that mean that everything is set right.

Sorry for the noob question.............

Thanks
Tim

Title: Re: A4000 CPU cards
Post by: beller on November 25, 2008, 04:37:36 PM

@Sandman

Looks like you've got everything set properly.  I say that because it booted and you're getting a reading that the '040 is up and running at proper speed.

My experience with the cpu card is if something, jumper etc. is amiss, you won't have a booting computer.