Datasheet

 1998-2013 Microchip Technology Inc. DS30289C-page 227
PIC17C7XX
SWAPF Swap f
Syntax: [ label ] SWAPF f,d
Operands: 0  f  255
d  [0,1]
Operation: f<3:0>  dest<7:4>;
f<7:4>  dest<3:0>
Status Affected: None
Encoding:
0001 110d ffff ffff
Description:
The upper and lower nibbles of register
'f' are exchanged. If 'd' is 0, the result is
placed in WREG. If 'd' is 1, the result is
placed in register 'f'.
Words: 1
Cycles: 1
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register 'f'
Process
Data
Write to
destination
Example:
SWAPF REG, 0
Before Instruction
REG = 0x53
After Instruction
REG = 0x35
TABLRD Table Read
Syntax: [ label ] TABLRD t,i,f
Operands: 0  f  255
i [0,1]
t [0,1]
Operation: If t = 1,
TBLATH  f;
If t = 0,
TBLATL  f;
Prog Mem (TBLPTR)  TBLAT;
If i = 1,
TBLPTR + 1  TBLPTR
If i = 0,
TBLPTR is unchanged
Status Affected: None
Encoding:
1010 10ti ffff ffff
Description:
1. A byte of the table latch (TBLAT)
is moved to register file 'f'.
If t = 1: the high byte is moved;
If t = 0: the low byte is moved.
2. Then, the contents of the pro-
gram memory location pointed to
by the 16-bit Table Pointer
(TBLPTR) are loaded into the
16-bit Table Latch (TBLAT).
3. If i = 1: TBLPTR is incremented;
If i = 0: TBLPTR is not
incremented.
Words: 1
Cycles: 2 (3-cycle if f = PCL)
Q Cycle Activity:
Q1 Q2 Q3 Q4
Decode Read
register
TBLATH or
TBLATL
Process
Data
Write
register 'f'
No
operation
No
operation
(Table Pointer
on Address
bus)
No
operation
No
operation
(OE
goes low)