Hi Robert,

 

I tested a long-TREQ and multi-TACK situation for GTRC-7 FPGA with a command sequence illustrated below.

I sent three TACK signals during one TREQ high with a duration of 10,000 clock cycles (500 us) and a TACK signal at the TREQ falling edge.

 

#CLK   0      1000                                    10,000

TREQ __-----------------------------------------------_______

TACK ____-___________-_______-________________________-______

         1st         2nd     3rd                      4th

TOKEN______-_______________________-______-_____________-____

           1st                     2nd    3rd           4th

 

 

I received data like following.

 

1st data: correct hit-strip data with TOT=1000

2nd data: correct hit-strip data with TOT=2044 (0x11111111100)

3rd data: correct hit-strip data with TOT=2044

4th data: correct hit-strip data with TOT=0

 

The TOT value of 2044 looks something like error code.  The response time for every TOKEN signal was less than 1000 clock cycle.  That should be correct behavior.  I also tried all possible patterns of event-tag number and checked that the response does not depend on the event-tag number.

 

Please ask me if you have any questions,

Mutsumi