Experimental Physics and
Industrial Control System

Hi EPICS folks,

     I am using EPICS 3.14.11 and TPMAC module version 3-7 with the Turbo PMAC (TPMAC) from Delta Tau to control motors for a new x-ray scanning microscope. We are using 2 TPMAC VME boards, both set for VME interrupt level 2 with different interrupt vectors 0xA1 and 0xA5. We have firmware version 1.945 for the TPMAC boards. The TPMAC CPUs are supposed to handle up to 180 MHz clock speed. For these TPMAC VME boards, we have been using a setting of 7 for the CPU frequency control variable I52, equivalent to 80 MHz clock speed. This works. When I increased this to 15, equivalent to 160 MHz, for both boards I see significant delays (~1 minute) in the time for the mailbox communications to reach one of the VME boards to initiate things such as starting a motion program. We are not seeing any evidence that the watchdog timer is resetting the TPMAC cpu (a symptom of trying to drive the cpu faster than possible according to the Delta Tau software documentation).

 

     Has anybody else seen such problems? So far, Delta Tau has not explained why this is happening.

 

Cheers,

Jay Steele

Xradia Corporation