The B12 is a VMEbus single Eurocard industrial computer designed to operate under harsh environmental conditions, e.g. in trains.The B12 is controlled by a PowerPC MPC823e microprocessor which operates at 66MHz. It provides 32MB SDRAM for data and up to 32MB Flash memory for program storage.32KB non-volatile FRAM can be used to periodically store operating data. There is no loss of operating data if system power is switched off.The B12 gives access to the serial communication ports of the MPC823e. These include two RS232 ports and a 10Base-T Ethernet interface on the board. In addition, the B12 offers three CAN controllers and an RS422/485 interface which can be used via ribbon-cable connection or directly using external SA adapters accessible at the front panel. All of these interfaces are optically isolated.The B12 board is prepared for master and slave operations on the VMEbus. It is equipped with a real-time clock, temperature sensor and a voltage supervisor. Board configuration data is stored in a 4kbit serial EEPROM.