Multiplication Instructions
Instruction Description
MUL.B Integer unsigned byte multiply F and WREG0
MUL{.W} Integer unsigned word multiply F and WREG0
MULL.SS Integer 16x16 Signed multiply
MULL.US Integer 16x16 Unsigned-Signed Multiply
MULL.UU Integer 16x16 Unsigned Multiply
MULL.UU Integer 16x16 Unsigned-Unsigned Short Literal Multiply
MULL.SU Integer 16x16 Signed-Unsigned Short Literal Multiply
  • WREG Multiply ( MUL.B or MUL.W)
    • Always uses WREG0 and any file register
    • Supports 8x8 multiply, generates 16-bit product
    • Results stored in W2 ( MUL.B ) or W3:W2 (MUL.W)
    • Provides PIC® MCU backward compatibility
  • 16-bit Integer Multiplication
    • Unsigned, Signed modes support W * W multiplies
      • MUL.UU, MUL.SS,
    • Mixed mode – supports W * short (5-bit) literal multiplies
      • MUL.US and MUL.SU
    • 32-bit Product is stored in adjacent working registers
      • W1:W0, W3:W2, … , W13:W12

MUL Example


MUL = file * WREG0 so therefore a file location must be used.

MUL.SS Example


MUL.SS can multiply two WREGs, and the second operand can be used as a pointer if desired. That is, you can have an instruction of the form w0, [w1], w2

© 2024 Microchip Technology, Inc.
Notice: ARM and Cortex are the registered trademarks of ARM Limited in the EU and other countries.
Information contained on this site regarding device applications and the like is provided only for your convenience and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. MICROCHIP MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO THE INFORMATION, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, PERFORMANCE, MERCHANTABILITY OR FITNESS FOR PURPOSE. Microchip disclaims all liability arising from this information and its use. Use of Microchip devices in life support and/or safety applications is entirely at the buyer's risk, and the buyer agrees to defend, indemnify and hold harmless Microchip from any and all damages, claims, suits, or expenses resulting from such use. No licenses are conveyed, implicitly or otherwise, under any Microchip intellectual property rights.