PIC instruction listings

The PIC instruction set is the set of instructions that Microchip Technology PIC or dsPIC microcontroller supports. The instructions are usually programmed into the Flash memory of the processor, and automatically executed by the microcontroller on startup.

PICmicro chips have a Harvard architecture and instruction words have unusual sizes. Originally, 12-bit instructions included 5 address bits to specify the memory operand, and 9-bit branch destinations. Later revisions added opcode bits, allowing additional address bits.

They are accumulator machines, with a common accumulator "W" being one operand in all 2-operand instructions.

In the instruction set tables that follow, register numbers are referred to as "f", while constants are referred to as "k". Bit numbers (0–7) are selected by "b". Arithmetic instructions write their result to one of the inputs selected by the "d" bit: 0 indicates W, while 1 indicates that the result is written back to source register f. The C and Z status flags may be set based on the result; otherwise they are unmodified. Add and subtract (but not rotate) instructions that set C also set the DC (digit carry) flag, the carry from bit 3 to bit 4, which is useful for BCD arithmetic.

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