Datasheet

dsPIC33EPXXX(GP/MC/MU)806/810/814 and PIC24EPXXX(GP/GU)810/814
DS70616F-page 482 Preliminary © 2009-2012 Microchip Technology Inc.
Most instructions are a single word. Certain double-
word instructions are designed to provide all the
required information in these 48 bits. In the second
word, the 8 MSbs are ‘0’s. If this second word is exe-
cuted as an instruction (by itself), it executes as a NOP.
The double-word instructions execute in two instruction
cycles.
Most single-word instructions are executed in a single
instruction cycle, unless a conditional test is true, or the
program counter is changed as a result of the
instruction, or a PSV or table read is performed. In these
cases, the execution takes multiple instruction cycles
with the additional instruction cycle(s) executed as a
NOP. Certain instructions that involve skipping over the
subsequent instruction require either two or three cycles
if the skip is performed, depending on whether the
instruction being skipped is a single-word or two-word
instruction. Moreover, double-word moves require two
cycles.
Note: For more details on the instruction set,
refer to the “16-bit MCU and DSC
Programmer’s Reference Manual”
(DS70157).
TABLE 30-1: SYMBOLS USED IN OPCODE DESCRIPTIONS
Field Description
#text Means literal defined by “text”
(text) Means “content of text”
[text] Means “the location addressed by text”
{ } Optional field or operation
a ∈ {b, c, d} a is selected from the set of values b, c, d
<n:m> Register bit field
.b Byte mode selection
.d Double-Word mode selection
.S Shadow register select
.w Word mode selection (default)
Acc One of two accumulators {A, B}
AWB Accumulator write back destination address register ∈ {W13, [W13]+ = 2}
bit4 4-bit bit selection field (used in word addressed instructions) ∈ {0...15}
C, DC, N, OV, Z MCU Status bits: Carry, Digit Carry, Negative, Overflow, Sticky Zero
Expr Absolute address, label or expression (resolved by the linker)
f File register address ∈ {0x0000...0x1FFF}
lit1 1-bit unsigned literal ∈ {0,1}
lit4 4-bit unsigned literal ∈ {0...15}
lit5 5-bit unsigned literal ∈ {0...31}
lit8 8-bit unsigned literal ∈ {0...255}
lit10 10-bit unsigned literal ∈ {0...255} for Byte mode, {0:1023} for Word mode
lit14 14-bit unsigned literal ∈ {0...16384}
lit16 16-bit unsigned literal ∈ {0...65535}
lit23 23-bit unsigned literal ∈ {0...8388608}; LSb must be ‘0’
None Field does not require an entry, can be blank
OA, OB, SA, SB DSP Status bits: ACCA Overflow, ACCB Overflow, ACCA Saturate, ACCB Saturate
PC Program Counter
Slit10 10-bit signed literal ∈ {-512...511}
Slit16 16-bit signed literal ∈ {-32768...32767}
Slit6 6-bit signed literal ∈ {-16...16}
Wb Base W register ∈ {W0...W15}
Wd Destination W register ∈ { Wd, [Wd], [Wd++], [Wd--], [++Wd], [--Wd] }
Wdo Destination W register ∈
{ Wnd, [Wnd], [Wnd++], [Wnd--], [++Wnd], [--Wnd], [Wnd+Wb] }
Wm,Wn Dividend, Divisor working register pair (direct addressing)