Microchip Technology MA330019-2 Data Sheet

© 2007-2012 Microchip Technology Inc.

DS70292G-page 325

The dsPIC33F instruction set is identical to that of the
dsPIC30F. 
Most instructions are a single program memory word
(24 bits). Only three instructions require two program
memory locations. 
Each single-word instruction is a 24-bit word, divided
into an 8-bit opcode, which specifies the instruction
type and one or more operands, which further specify
the operation of the instruction. 
The instruction set is highly orthogonal and is grouped
into five basic categories:
• Word or byte-oriented operations
• Bit-oriented operations
• Literal operations
• DSP operations
• Control operations

 shows the general symbols used in

describing the instructions. 
The dsPIC33F instruction set summary in 

lists all the instructions, along with the status flags
affected by each instruction. 
Most word or byte-oriented W register instructions
(including barrel shift instructions) have three
operands: 
• The first source operand, which is typically a 

register ‘Wb’ without any address modifier

• The second source operand, which is typically a 

register ‘Ws’ with or without an address modifier

• The destination of the result, which is typically a 

register ‘Wd’ with or without an address modifier 

However, word or byte-oriented file register instructions
have two operands:
• The file register specified by the value ‘f’
• The destination, which could be either the file 

register ‘f’ or the W0 register, which is denoted as 
‘WREG’

Most bit-oriented instructions (including simple rotate/
shift instructions) have two operands:
• The W register (with or without an address 

modifier) or file register (specified by the value of 
‘Ws’ or ‘f’) 

• The bit in the W register or file register (specified 

by a literal value or indirectly by the contents of 
register ‘Wb’) 

The literal instructions that involve data movement can
use some of the following operands:
• A literal value to be loaded into a W register or file 

register (specified by ‘k’) 

• The W register or file register where the literal 

value is to be loaded (specified by ‘Wb’ or ‘f’)

However, literal instructions that involve arithmetic or
logical operations use some of the following operands:
• The first source operand, which is a register ‘Wb’ 

without any address modifier

• The second source operand, which is a literal 

value

• The destination of the result (only if not the same 

as the first source operand), which is typically a 
register ‘Wd’ with or without an address modifier

The MAC class of DSP instructions can use some of the
following operands:
• The accumulator (A or B) to be used (required 

operand)

• The W registers to be used as the two operands
• The X and Y address space prefetch operations
• The X and Y address space prefetch destinations
• The accumulator write back destination
The other DSP instructions do not involve any
multiplication and can include:
• The accumulator to be used (required)
• The source or destination operand (designated as 

Wso or Wdo, respectively) with or without an 
address modifier 

• The amount of shift specified by a W register ‘Wn’ 

or a literal value

The control instructions can use some of the following
operands:
• A program memory address 
• The mode of the table read and table write 

instructions 

This data sheet summarizes the features
of the dsPIC33FJ32GP302/304,
dsPIC33FJ64GPX02/X04, and
dsPIC33FJ128GPX02/X04 families of
devices. It is not intended to be a compre-
hensive reference source. To complement
the information in this data sheet, refer to
the “dsPIC33F/PIC24H Family Reference
Manual”. Please see the Microchip web
site (

www.microchip.com

) for the latest

reference manual sections.