Experimental Physics and
Industrial Control System

Torsten Bögershausen <[email protected]> · Thu, 8 May 2014 08:13:42 +0200

On 5/7/14 11:32 PM, Johnson, Andrew N. wrote:

Hi Mark,

You could try adding a call to the gcc built-in routine __sync_synchronize(); after the last write to the asynUser structure. This implements a full memory barrier, which is equivalent to the two memory barriers inside the mutex operations. If this fixes it for ARM there is probably a better solution, but this will at least identify if this is the cause of the problem.

This would be needed on a multi-core system.

What system is in use ?
single core or multi core?

I just got the motor simulator working on the Raspberry PI, (after some days of debugging)
The trick was to use this block in motorApp/MotorSrc/motor.h:

==============
/* Define, from top to bottom, how bit fields are packed. */
/* This works for gnu, SunPro, MS Visual C. */
#include <epicsEndian.h>
#if (EPICS_BYTE_ORDER == EPICS_ENDIAN_LITTLE)
    #define LSB_First (TRUE)
    #warning LSB_First
#endif

#if (EPICS_BYTE_ORDER == EPICS_ENDIAN_BIG)
    #define MSB_First (TRUE)
    #warning MSB_First
#endif

===============

What do you get when you compile with this change ? MSB_First or LSB_First ?

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System