The GGLT interface provides an internal self trigger routine. After all the hardware is configured and the event processing loop is running the user can call the self trigger from another VxWorks task. Calling the self trigger looks like this:
status = ggSelfTrg( gg); |
Calling this function begins the following sequence of steps:
A trigger message is formed in the GGLT using the current trigger message configuration. This message includes a new event number.
The trigger message is sent from the GGLT to the TEM board.
The TEM decodes the trigger message and forwards it on to the appropriate electronics ( cable controllers, front end electronics, etc... ).
The front end electronics trigger and send data back to the TEM
The TEM packages the event data and sends it to the GGLT LAT COMM I/O Board.
The GGLT calls the user supplied memory allocator for a buffer to hold the event data.
The GGLT reads the data from the LAT COMM I/O Board and stores it the buffer.
The GGLT calls the user supplied event handling routine, passing in the event buffer.
The event handler routine processes the event data in a user defined way.
The event handler decides whether to continue processing more events by returning a non-zero value or not.
In between triggers the user is allowed to change the GTEM configuration or the GGLT configuration.