BRX expansion modules add discrete I/O, analog I/O and high-speed I/O and communications functions as needed to expand machine and process control applications. The modules snap onto the side of any BRX Micro PLC unit (MPU). Two high-speed (HSIO) discrete I/O modules are available with eight 12- to 24-Vdc sink/source inputs and either eight 12- to 24-Vdc sink outputs or eight 12- to 24-Vdc source outputs. These modules are capable of up to 250-kHz high-speed input/output signals.