1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 <2011> 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 | Index | 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 <2011> 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 |
<== Date ==> | <== Thread ==> |
---|
Subject: | comm delays caused by setting TPMAC VME CPU clock to max speed |
From: | Jay Steele <[email protected]> |
To: | "[email protected]" <[email protected]> |
Cc: | Claus Flachenecker <[email protected]>, Zhenyang Chen <[email protected]> |
Date: | Fri, 4 Feb 2011 15:10:26 -0800 |
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 The information in this email, including any attachments, is confidential and intended only for the recipient(s) listed. Any use of this email for any other purpose is prohibited. If you have received this email in error, please notify me immediately by reply email, delete this email, and do not disclose its contents to anyone. |