PIC18F2221 MICROCHIP [Microchip Technology], PIC18F2221 Datasheet - Page 289

• Manufacturer Part Number: PIC18F2221
• Description: 28/40/44-Pin Enhanced Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

BTG
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
© 2007 Microchip Technology Inc.
Q Cycle Activity:
Before Instruction:
After Instruction:
Decode
PORTC =
PORTC =
Q1
register ‘f’
BTG
Bit Toggle f
BTG f, b {,a}
0 ≤ f ≤ 255
0 ≤ b < 7
a ∈ [0,1]
(f<b>) → f<b>
None
Bit ‘b’ in data memory location ‘f’ is
inverted.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 24.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
1
1
Read
0111
Q2
0111 0101 [75h]
0110 0101 [65h]
PORTC,
bbba
Process
Data
Q3
4, 0
ffff
register ‘f’
Write
Q4
ffff
Preliminary
BOV
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
Q Cycle Activity:
If Jump:
If No Jump:
PIC18F4321 FAMILY
Before Instruction
After Instruction
operation
Decode
Decode
PC
If Overflow
If Overflow
Q1
No
Q1
PC
PC
Read literal
Read literal
operation
Branch if Overflow
BOV
-128 ≤ n ≤ 127
if Overflow bit is ‘1’
(PC) + 2 + 2n → PC
None
If the Overflow bit is ‘1’, then the
program will branch.
The 2’s complement number ‘2n’ is
added to the PC. Since the PC will have
incremented to fetch the next
instruction, the new address will be
PC + 2 + 2n. This instruction is then a
two-cycle instruction.
1
1(2)
HERE
1110
Q2
Q2
No
‘n’
‘n’
=
=
=
=
=
n
address (HERE)
1;
address (Jump)
0;
address (HERE + 2)
0100
BOV
operation
Process
Process
Data
Data
Q3
No
Q3
DS39689E-page 287
Jump
nnnn
Write to PC
operation
operation
Q4
Q4
No
No
nnnn