The APS3R is the workhorse of the Cortus processor family designed specifically to meet the needs of embedded systems. The APS3R is an enhanced version of the APS3, providing improved performance for a fractional increase in silicon area. All instructions are 16 bits in length, with a 16 bit extension when needed (no mode switches necessary) providing excellent code density. The pipeline features out-of-order execution enabling nearly all instructions to execute in a single cycle, including loads and stores. Interrupts are fully vectored and the architecture ensures a minimum of software overhead in task switches. The processor was designed to execute high level languages with excellent efficiency.