The DSPIC33FJ128GP804-I/PT is a 16-bit Digital Signal Controller with advanced analogue. The CPU module has a 16-bit (data) modified Harvard architecture with an enhanced instruction set, including significant support for DSP. The CPU has a 24-bit instruction word with a variable length opcode field. The Program Counter (PC) is 23-bit wide and addresses up to 4M x 24-bit of user program memory space. The actual amount of program memory implemented varies by device. A single-cycle instruction prefetch mechanism is used to help maintain throughput and provides predictable execution. All instructions execute in a single cycle, with the exception of instructions that change the program flow, the double-word move (MOV.D) instruction and the table instructions. Overhead-free program loop constructs are supported using the DO and REPEAT instructions, both of which are interruptible at any time.