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Executive Crate Controller

The executive crate controller (ECC) is a special type of crate controller. It controls the operations of the entire CAMAC system.

A cycle starts when the ECC arbitrates which computer will give the next command. After it receives the command from the computer, it checks the B and C values to see where the command is to go. If the command is for a module in the system crate (indicated by B = 0 and C = 0), then the ECC checks the N value and sends it down to the correct module. If the command is intented for a module not in the system crate, then the ECC will use the appropriate branch coupler to send the command to the correct branch, crate, and module.

The ECC controls the timing of the system crate, and takes data from one branch coupler at a time. When experimental data comes to the system crate through a branch coupler, the ECC directs the data to the correct computer.