The tracker is operated through a TEM board on a VME crate called TKR VME. The tracker can be configured, operated, and readout with the TKR VME system through Ethernet. In response to an event trigger or upon our request sent through Ethernet, the TEM board sends out commands to controller chips on HDI's and reads their responses. The responses include hit information during normal operation. The TEM board interprets the hit information, reformat them, and put them into an event FIFO, which is visible in a VME memory space.
In sections below, tracker readout procedure is briefly explained. Also, a control register of a front-end chip, that of a controller chip, and addressing scheme for both chips are described.