PIC24FJ16MC101_12 Datasheet, PDF (244/350 Pages) Microchip Technology – 16-bit Microcontrollers (up to 32 KB Flash and 2 KB SRAM)

PIC24FJ16MC101/102 AND PIC24FJ32MC101/102/104
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 will execute 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 instruc-
tion. In these cases, the execution takes two instruction
cycles with the additional instruction cycle(s) executed
as a NOP. Notable exceptions are the BRA (uncondi-
tional/computed branch), indirect CALL/GOTO, all table
reads and writes and RETURN/RETFIE instructions,
which are single-word instructions but take two or three
cycles. 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 Pro-
grammer’s Reference Manual (DS70157).
TABLE 24-1: SYMBOLS USED IN OPCODE DESCRIPTIONS
Field
Description
#text
(text)
[text]
{}
<n:m>
.b
.d
.S
.w
Acc
AWB
bit4
C, DC, N, OV, Z
Expr
f
lit1
lit4
lit5
lit8
lit10
lit14
lit16
lit23
None
OA, OB, SA, SB
PC
Slit10
Slit16
Slit6
Wb
Wd
Wdo
Wm,Wn
Means literal defined by “text”
Means “content of text”
Means “the location addressed by text”
Optional field or operation
Register bit field
Byte mode selection
Double-Word mode selection
Shadow register select
Word mode selection (default)
One of two accumulators {A, B}
Accumulator write back destination address register ∈ {W13, [W13]+ = 2}
4-bit bit selection field (used in word addressed instructions) ∈ {0...15}
MCU Status bits: Carry, Digit Carry, Negative, Overflow, Sticky Zero
Absolute address, label or expression (resolved by the linker)
File register address ∈ {0x0000...0x1FFF}
1-bit unsigned literal ∈ {0,1}
4-bit unsigned literal ∈ {0...15}
5-bit unsigned literal ∈ {0...31}
8-bit unsigned literal ∈ {0...255}
10-bit unsigned literal ∈ {0...255} for Byte mode, {0:1023} for Word mode
14-bit unsigned literal ∈ {0...16384}
16-bit unsigned literal ∈ {0...65535}
23-bit unsigned literal ∈ {0...8388608}; LSb must be ‘0’
Field does not require an entry, can be blank
DSP Status bits: ACCA Overflow, ACCB Overflow, ACCA Saturate, ACCB Saturate
Program Counter
10-bit signed literal ∈ {-512...511}
16-bit signed literal ∈ {-32768...32767}
6-bit signed literal ∈ {-16...16}
Base W register ∈ {W0..W15}
Destination W register ∈ {Wd, [Wd], [Wd++], [Wd--], [++Wd], [--Wd]}
Destination W register ∈
{Wnd, [Wnd], [Wnd++], [Wnd--], [++Wnd], [--Wnd], [Wnd+Wb]}
Dividend, Divisor working register pair (direct addressing)
DS39997C-page 244
Preliminary
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