PIC18F2221 MICROCHIP [Microchip Technology], PIC18F2221 Datasheet - Page 284

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

PIC18F4321 FAMILY
BCF
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
DS39689E-page 282
Q Cycle Activity:
Before Instruction
After Instruction
Decode
FLAG_REG =
FLAG_REG =
Q1
register ‘f’
Bit Clear f
BCF
0 ≤ f ≤ 255
0 ≤ b ≤ 7
a ∈ [0,1]
0 → f<b>
None
Bit ‘b’ in register ‘f’ is cleared.
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
BCF
Read
1001
Q2
f, b {,a}
C7h
47h
FLAG_REG,
bbba
Process
Data
Q3
ffff
7, 0
register ‘f’
Write
Q4
ffff
Preliminary
BN
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
Q Cycle Activity:
If Jump:
If No Jump:
Before Instruction
After Instruction
operation
Decode
Decode
PC
If Negative
If Negative
Q1
No
Q1
PC
PC
Read literal
Read literal
operation
Branch if Negative
BN
-128 ≤ n ≤ 127
if Negative bit is ‘1’
(PC) + 2 + 2n → PC
None
If the Negative 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
No
Q2
‘n’
‘n’
=
=
=
=
=
© 2007 Microchip Technology Inc.
n
address (HERE)
1;
address (Jump)
0;
address (HERE + 2)
0110
BN
operation
Process
Process
Data
Data
Q3
No
Q3
Jump
nnnn
Write to PC
operation
operation
Q4
No
Q4
No
nnnn