When the TRIG command is issued, the system produces 2 packets of data, 63 words long, plus 6 header and 2 trailed marker words each. The reason 2 packets are sent is that the correlator is, for the moment, hardwired off. The data are sent over the J2 connector to the LeCroy 4302 memory module. After this is done, an extra pulse is sent to a camac NIM output module in camac slot 17. The strobe output of this module is connected to the INT4 spigot on the camac interface module in the VME crate. This arrangement triggers CODA readout of the LeCroy 4302 memory module. In the beam test, the same arrangement will be used for the FEE readout, but of course the trigger signal will not be computer-generated.
The data received in
the coda analyzer program have been checked to be identical to those generated
by the HM board. Relevant CODA software is located in ~/coda/run, files
test\_camlist.crl and ebana\_test.f, and in ~/coda/rcDatabase, files rcNetwork
and physics.config.