MWPC readout with the GPX ASIC

For X-ray spectroscopy at the plasma physics tokamak TEXTOR in Forschungszentrum Julich a TDC module has been developed for the readout of multi-wire proportional counters (MWPC). The new board comes in CompactPCI form factor and is based on the GPX TDC ASIC from acam messelectronic GmbH. In the selected mode I-mode the GPX has 8 input channels with a typical resolution of 81 ps. The implemented software consists of a Linux device driver and a measurement application program. The Linux device driver is responsible for the transfer of list-mode data via DMA into the main memory of a PC. After each TEXTOR shot the application program transfers the data from RAM to disk and automatically adds administrative shot information.