Electronics commissioning experience at HERA-B

The readout of HERA-B has been unified to a large extension. Only the HELIX and ASD8 chips with corresponding readout electronics were used and the data acquisition is constructed entirely with Sharc DSPs. This approach minimized the work load and was successful. The feedback of the ASD8 digital outputs to the analog inputs caused oscillations and the efforts to solve this problem still continued in the commissioning phase. The electronics of the sophisticated hardware trigger was commissioned successfully while some problems remain with the self-made 900 Mbit optical data transmission. (14 refs).