KDJ11-AA upgrade for FPJ11

[jmdhuse]

Hello All,

I see in various places that the KDJ11-AA CPU module had a flaw that rendered it incompatible with the FPJ11 floating point accelerator component, but that it could be upgraded to be compatible.

From micronote25:

"The KDJ11-AA can be upgraded to be FPJ11-AA compatible. Contact the local DEC office for more information concerning the upgrade procedure."

Does anyone know what the upgrade entailed? Was is simple a matter of replacing the CPU component with a later version?

Thanks, Jon.

 

[cruff]

Here is a DEC Micronote about it, but no information about the procedure, which may have just been a board swap. http://www.ibiblio.org/pub/academic...hardware/micronotes/numerical/micronote25.txt

The KDJ11-A CPU Module User's Guide mentions cache and DMA errors if the FPJ11-AA is installed on a KDJ11-AA board.

 

[Steve Toner]

Apparently a non-trivial upgrade.

From https://gunkies.org/wiki/KDJ11_CPUs:

(The issue with the early KDJ11-A is that early revisions have bugs in their gate array chips which prevent correct operation of the FPJ11.)

 

[jmdhuse]

Apparently a non-trivial upgrade.

From https://gunkies.org/wiki/KDJ11_CPUs:

Ahhhh, problem with the gate array... I instantly will give up the idea of searching for a FP component to add to my KDJ11-AA (which has an upgraded CPU component).... Thanks!