STEREO/HET/SIT Configuration Tracking Form

To be filled in by configuration manager:

 

Tracking Number:  00018         Date Received:   07/11/04

 

To be filled in by initiator:

 

Software Type:    Flight Software               Instrument Name:    HET

           

Version Name:  20040701                        Type of Action:   Problem Report  (PR)

Initiator's Name: Larry Ryan/Kristin Wortman              Date Initiated:  07/11/04

 

To be filled in by initiator:

 

Description of action(s)/problems(s): 

 

When the coincidence rate (number of events is incremented), a packet with ApId 596 (diagnostics packet) is generated.   The sw recovers when the coincidence rate is decreased.

To be filled in by Programmer:

 

Software Version Name:             FSW_HET_20040722

                                   

Programmer(s) Name:         Kristin Wortman

 

Date Completed:       07/22/04

 

Modules/Routines affected:    penevnts.p24, proc.p24

 

 

Comments:   Apparently when the coincidence rate is increased, the crosstalk problem increases and is seen through the H6 detector.    Since the crosstalk exhibits a  ph value less than the offset correction value, the result is forced to 0, however the event is still considered to be a penetrating event  and should be processed.   The correct event type would be a stopping event without the crosstalk.  The H6 value is used as an index into the tables,  0 being  on the lower boundary.  The processing code errored when checking the lower boundary condition and executed code for an incorrect boundary value and did not properly clean the parameter stack.   The packet identified with ApId  596 is generated as a diagnostic dump when the stack has overflowed.