PIC18F2450 MICROCHIP [Microchip Technology], PIC18F2450 Datasheet - Page 222

• Manufacturer Part Number: PIC18F2450
• Description: 28/40/44-Pin, High-Performance, 12 MIPS, Enhanced Flash, USB Microcontrollers with nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2450/4450
BCF
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
DS39760A-page 220
Q Cycle Activity:
Before Instruction
After Instruction
Decode
FLAG_REG =
FLAG_REG =
Q1
register ‘f’
Bit Clear f
BCF
0
0
a
0
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
Section 19.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
1
1
BCF
Read
1001
Q2
f
b
[0,1]
f<b>
255
7
f, b {,a}
C7h
47h
FLAG_REG,
bbba
Process
Data
Q3
95 (5Fh). See
ffff
7, 0
register ‘f’
Advance Information
Write
Q4
ffff
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
No
Q1
Q1
PC
PC
Read literal
Read literal
operation
Branch if Negative
BN
-128
if Negative bit is ‘1’
(PC) + 2 + 2n
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
No
‘n’
‘n’
Q2
Q2
=
=
=
=
=
© 2006 Microchip Technology Inc.
n
n
address (HERE)
1;
address (Jump)
0;
address (HERE + 2)
127
0110
operation
BN
Process
Process
Data
Data
No
PC
Q3
Q3
Jump
nnnn
Write to PC
operation
operation
No
No
Q4
Q4
nnnn