This discussion explains the instructions for the PIC12F629 and PIC16F628.

addlw number

• adds a number (called a literal - 00 to FF) to the number in the working register.

addwf FileReg, f

• adds the number in the working register to the number in a file (FileReg) and puts the result in the file.

addwf FileReg, w

• adds the number in the working register to the number in a file (FileReg) and puts the result back into the working register, leaving the file register unchanged.

andlw number

• ANDs a number to the number in the working register, leaving the result in the working reg.

andwf FileReg, f

• ANDs the number in the working register to the number in a file (FileReg) and puts the result in the file register

bcf FileReg, bit

• clears a bit in a file (FileReg), i.e. makes the bit 0

bsf FileReg, bit

• sets a bit in a file (FileReg), i.e. makes the bit 1

btfsc FileReg, bit

• tests a bit in a file (FileReg) and skips the next instruction if the result is clear (i.e. if that bit is 0).

btfss FileReg, bit

• tests a bit in a file (FileReg) and skips the next instruction if the result is set (i.e. if that bit is 1).

call label

• makes the chip call any label, after which it will return to where it left off if the sub-routine contains retlw 00.

clrf File

• clears (makes 0) the number in a file (FileReg).

clrw

• clears the working register.

clrwdt

• clears the watchdog timer.

comf FileReg, f

• complements (inverts - ones become zeroes, zeroes become ones) the number in a file (FileReg), leaving the result in the file register.

decf FileReg, f

• decrements (subtracts one from) a file (FileReg) and puts the result in the file register.

decfsz FileReg, f

• decrements a file (FileReg) and if the result is zero it skips the next instruction. The result is put in the file.

goto Label

• makes the chip go to a label in the program.

incf FileReg, f

• increments (adds one to) a file (FileReg) and puts the result in the file.

incfsz FileReg, f

• increments a file(FileReg) and if the result is zero it skips the next instruction. The result is put in the file.

iorlw number

• inclusive ORs a number with the number in the working register.

iorwf FileReg, f

• inclusive ORs the number in the working register with the number in a file(FileReg) and puts the result in the file.

movfw FileReg or movf FileReg, w

• moves (copies) the number in a file(FileReg) in the working register

movlw number

• puts a number into the working register.

movwf FileReg

• moves (copies) the number in the working register into a file (FileReg).

nop

• this stands for : no operation, in other words - do nothing, (it is used to create a delay)

option_reg

• takes the number in the working register and moves it into the option register.

retfie

• (NOT FOR PIC16C5X SERIES) - returns from a subroutine and enables the Global Interrupt Enable bit.

retlw number

• returns from a subroutine with a number (literal) (from 00 to FF) in the working register.

rlf FileReg, f

• rotates the bits in a file (FileReg) to the left, putting the result in the file.

rrf FileReg, f

• rotates the bits in a file(FileReg) to the right, putting the result in the file.

sleep

• sends the PIC to sleep, a lower power consumption mode.

sublw number

• subtracts the number in the working register from a literal. To subtract 1 from W, use: addlw 255

subwf FileReg, f

• subtracts the number in the working register from the number in a file (FileReg) and puts the result in the file.

swapf FileReg, f

• swaps the two halves of the 8 bit binary number in a file (FileReg), leaving the result in the file.

movwf tris PORTA or movwf trisPORTB or movwf trisio for PIC12F629

• moves the value in w to the tris file.

xorlw number

• exclusive ORs a literal with the number in the working register.

xorwf FileReg, f

• exclusive ORs the number in the working register with the number in a file (FileReg) and puts the result in the file.