Here, I report the status of WFD tests at Gran Sasso as well as progresses
and problems. This is just first stage test.
I have performed these tests:
(1) Zero Suppression Enable OK! Measured the outputs of flip-flops
(2) Interrupt Enable OK! "
(3) Address Enable OK! "
(4) Rollover Enable OK! "
(5) Stop Enable OK! "
(6) Read_only/WR_RD OK! measured flip-flop, detail tests
(7) DAC Clock ? measured flip-flop, but not sure yet
The VME computer system, VIC interface system, TAMU VME Crate+power system
are woking fine. The communication between the WFD board and VME computer
(include PASCAL software driver) is working fine as well.
I need more tests to say more about threshold setting and DAC Clock. But
at this moment, I feel it may have some problems.
When I started to test the WFDs I first used the CAMAC lists in bostonpub
account. There were about 5% of the times I could swap between read_only
and WR_RD mode correctly. What was the problem? I found that the
instructions which were used to write a byte to the control registers are like
these: "VME_WR_ST 1,2,$70FFE0,$04". The operation of setting control registers
requires a writting at the respective addresses, but only MOST SIGINIFICATE BYTE
of data is used! (VME bus has 32 bits data line, 4 bytes for a long word write)
. And Also, the VAX, interfaces, WFD interfaces, etc swap the 4 bytes of
data by a number of times. For safer, I modified the writting instructions
in the CAMAC lists to: "VME_WR_ST 1,2,$70FFE0,$04040404". Then, I got exactly
what I want (except DAC Clock). I mention this here to drive everybody's
attention, especially for the people who write software for Daq in the future.
It can be extremly painful.
Next, I need to make more detail tests for all the functions,
specially the threshold setting. At Texas A&M, we found some noise
problems. I need to test the noise levels at the MACRO enviroments.
Any commants, SUGGESTIONS for the on-site tests are welcome!!!
Regards,
Younan Lu, Gran Sasso