PIC16F628 Data (PIC16F628.pdf  -  2.6MB)

Start Here with PIC16F628

Although we have written Special Purpose Registers are located at 00 to 1F in the Instruction Set above (bank 0), they are also found in Bank 1. But you do not have to know their location or file number. 

When writing a program, simply use the full name (from the list below) and the the assembler will locate the file number during assembly.
Most assemblers have a built-in list with the names of all the registers and file numbers. For a PIC16F628, the list is:
P16F628A.inc   It is called a .inc file (include file).
When writing a program, place the following instructions at the top:

             LIST P=16F628A, F=INHX8M
             include "P16F628A.inc"
In the same folder where your program is located, place the .inc file. The assembler will find the .inc file, read the name you have given to each file, and produce a file number.

Below are the names of the files. Write them in your program in lower case thus:

      btfss       status,z       ;test the zero bit and skip if set

      movlw      46h            ;put 46h into w
      movwf      porta          ;output 46h via port A

      bsf          portb,2        ;output a high on the third line of port B

      bsf          status,rp0   ;Select Bank 1 where the tris and other files are located
      bsf          trisb,1        ;Make the second line of port B output
      bcf          status,rp0   ;Get back to Bank 0 where PortA and PortB is located
      movlw      88h            ; "1000 1000"
      movlw      portb

;       Register Definitions

W                            EQU     H'0000'
F                            EQU     H'0001'

;----- Register Files----------------------------------------------

INDF                         EQU     H'0000'
TMR0                         EQU     H'0001'
PCL                          EQU     H'0002'
STATUS                       EQU     H'0003'
FSR                          EQU     H'0004'
PORTA                        EQU     H'0005'
PORTB                        EQU     H'0006'
PCLATH                       EQU     H'000A'
INTCON                       EQU     H'000B'
PIR1                         EQU     H'000C'
TMR1L                        EQU     H'000E'
TMR1H                        EQU     H'000F'
T1CON                        EQU     H'0010'
TMR2                         EQU     H'0011'
T2CON                        EQU     H'0012'
CCPR1L                       EQU     H'0015'
CCPR1H                       EQU     H'0016'
CCP1CON                      EQU     H'0017'
RCSTA                        EQU     H'0018'
TXREG                        EQU     H'0019'
RCREG                        EQU     H'001A'
CMCON                        EQU     H'001F'

OPTION_REG                   EQU     H'0081'
TRISA                        EQU     H'0085'
TRISB                        EQU     H'0086'
PIE1                         EQU     H'008C'
PCON                         EQU     H'008E'
PR2                          EQU     H'0092'
TXSTA                        EQU     H'0098'
SPBRG                        EQU     H'0099'
EEDATA                       EQU     H'009A'
EEADR                        EQU     H'009B'
EECON1                       EQU     H'009C'
EECON2                       EQU     H'009D'
VRCON                        EQU     H'009F'

;----- STATUS Bits ------------------------------------------------

IRP                          EQU     H'0007'
RP1                          EQU     H'0006'
RP0                          EQU     H'0005'
NOT_TO                       EQU     H'0004'
NOT_PD                       EQU     H'0003'
Z                            EQU     H'0002'
DC                           EQU     H'0001'
C                            EQU     H'0000'

;----- INTCON Bits ------------------------------------------------

GIE                          EQU     H'0007'
PEIE                         EQU     H'0006'
T0IE                         EQU     H'0005'
INTE                         EQU     H'0004'
RBIE                         EQU     H'0003'
T0IF                         EQU     H'0002'
INTF                         EQU     H'0001'
RBIF                         EQU     H'0000'

;----- PIR1 Bits --------------------------------------------------

EEIF                         EQU     H'0007'
CMIF                         EQU     H'0006'
RCIF                         EQU     H'0005'
TXIF                         EQU     H'0004'
CCP1IF                       EQU     H'0002'
TMR2IF                       EQU     H'0001'
TMR1IF                       EQU     H'0000'

;----- T1CON Bits -------------------------------------------------
T1CKPS1                      EQU     H'0005'
T1CKPS0                      EQU     H'0004'
T1OSCEN                      EQU     H'0003'
NOT_T1SYNC                   EQU     H'0002'
TMR1CS                       EQU     H'0001'
TMR1ON                       EQU     H'0000'

;----- T2CON Bits -------------------------------------------------
TOUTPS3                      EQU     H'0006'
TOUTPS2                      EQU     H'0005'
TOUTPS1                      EQU     H'0004'
TOUTPS0                      EQU     H'0003'
TMR2ON                       EQU     H'0002'
T2CKPS1                      EQU     H'0001'
T2CKPS0                      EQU     H'0000'

;----- CCP1CON Bits -----------------------------------------------
CCP1X                        EQU     H'0005'
CCP1Y                        EQU     H'0004'
CCP1M3                       EQU     H'0003'
CCP1M2                       EQU     H'0002'
CCP1M1                       EQU     H'0001'
CCP1M0                       EQU     H'0000'

;----- RCSTA Bits -------------------------------------------------
SPEN                         EQU     H'0007'
RX9                          EQU     H'0006'
SREN                         EQU     H'0005'
CREN                         EQU     H'0004'
ADEN                         EQU     H'0003'
FERR                         EQU     H'0002'
OERR                         EQU     H'0001'
RX9D                         EQU     H'0000'

;----- CMCON Bits -------------------------------------------------

C2OUT                        EQU     H'0007'
C1OUT                        EQU     H'0006'
C2INV                        EQU     H'0005'
C1INV                        EQU     H'0004'
CIS                          EQU     H'0003'
CM2                          EQU     H'0002'
CM1                          EQU     H'0001'
CM0                          EQU     H'0000'

;----- OPTION Bits ------------------------------------------------

NOT_RBPU                     EQU     H'0007'
INTEDG                       EQU     H'0006'
T0CS                         EQU     H'0005'
T0SE                         EQU     H'0004'
PSA                          EQU     H'0003'
PS2                          EQU     H'0002'
PS1                          EQU     H'0001'
PS0                          EQU     H'0000'

;----- PIE1 Bits --------------------------------------------------

EEIE                         EQU     H'0007'
CMIE                         EQU     H'0006'
RCIE                         EQU     H'0005'
TXIE                         EQU     H'0004'
CCP1IE                       EQU     H'0002'
TMR2IE                       EQU     H'0001'
TMR1IE                       EQU     H'0000'

;----- PCON Bits --------------------------------------------------

OSCF                         EQU     H'0003'
NOT_POR                      EQU     H'0001'
NOT_BO                       EQU     H'0000'
NOT_BOR                      EQU     H'0000'
NOT_BOD                      EQU     H'0000' ;Backwards compatability to 16F62X

;----- TXSTA Bits -------------------------------------------------
CSRC                         EQU     H'0007'
TX9                          EQU     H'0006'
TXEN                         EQU     H'0005'
SYNC                         EQU     H'0004'
BRGH                         EQU     H'0002'
TRMT                         EQU     H'0001'
TX9D                         EQU     H'0000'

;----- EECON1 Bits ------------------------------------------------
WRERR                        EQU     H'0003'
WREN                         EQU     H'0002'
WR                           EQU     H'0001'
RD                           EQU     H'0000'

;----- VRCON Bits -------------------------------------------------

VREN                         EQU     H'0007'
VROE                         EQU     H'0006'
VRR                          EQU     H'0005'
VR3                          EQU     H'0003'
VR2                          EQU     H'0002'
VR1                          EQU     H'0001'
VR0                          EQU     H'0000'

;       RAM Definition

    __MAXRAM H'01FF'
    __BADRAM H'07'-H'09', H'0D', H'13'-H'14', H'1B'-H'1E'
    __BADRAM H'87'-H'89', H'8D', H'8F'-H'91', H'93'-H'97', H'9E'
    __BADRAM H'105', H'107'-H'109', H'10C'-H'11F', H'150'-H'16F'
    __BADRAM H'185', H'187'-H'189', H'18C'-H'1EF'

;       Configuration Bits

_BODEN_ON                    EQU     H'3FFF'
_BODEN_OFF                   EQU     H'3FBF'
_BOREN_ON                    EQU     H'3FFF'
_BOREN_OFF                   EQU     H'3FBF'
_CP_ON                       EQU     H'1FFF'
_CP_OFF                      EQU     H'3FFF'
_DATA_CP_ON                  EQU     H'3EFF'
_DATA_CP_OFF                 EQU     H'3FFF'
_PWRTE_OFF                   EQU     H'3FFF'
_PWRTE_ON                    EQU     H'3FF7'
_WDT_ON                      EQU     H'3FFF'
_WDT_OFF                     EQU     H'3FFB'
_LVP_ON                      EQU     H'3FFF'
_LVP_OFF                     EQU     H'3F7F'
_MCLRE_ON                    EQU     H'3FFF'
_MCLRE_OFF                   EQU     H'3FDF'
_RC_OSC_CLKOUT               EQU     H'3FFF'
_RC_OSC_NOCLKOUT             EQU     H'3FFE'
_ER_OSC_CLKOUT               EQU     H'3FFF'
_ER_OSC_NOCLKOUT             EQU     H'3FFE'
_EXTCLK_OSC                  EQU     H'3FEF'
_HS_OSC                      EQU     H'3FEE'
_XT_OSC                      EQU     H'3FED'
_LP_OSC                      EQU     H'3FEC'


ADDWF PCL,1  ADDWF 02,1   Alter the program counter to create a jump
CLRF INDF,1  CLRF 00,1    Clear INDIRECT file 
INCF FSR,1   INCF 04,1    Increment the File Select Register

INTCON address is either 0Bh or 8Bh - it is mapped at both locations.
BCF INTCON,RBIF    Clear RB<7:4> Port-change Interrupt flag
BSF INTCON,RBIF    Set RB<7:4> Port-change Interrupt flag
BCF INTCON,RBIE    Disables the Port-change Interrupt 
BSF INTCON,RBIE    Enables the Port-change Interrupt 
BCF INTCON,INTE    Disables the RB0/INT Interrupt 
BSF INTCON,INTE    Enables the RB0/INT Interrupt 
BCF INTCON,T0IE     Disables the TMR0 Interrupt 
BSF INTCON,T0IE     Enables the TMR0 Interrupt 
BCF INTCON,EEIE    Disables the EE write complete Interrupt 
BSF INTCON,EEIE    Enables the EE write complete Interrupt 
BCF INTCON,GIE      Disables all Interrupts
BSF INTCON,GIE      Enables all un-masked Interrupts

OPTION address is  81h - use the word OPTION
OPTION,0    OPTION,1   OPTION,2  Prescaler Rate Select Bits
Bit Value TMR0 Rate WDT Rate
BSF OPTION,0  BCF OPTION,1  BSF OPTION,2 TMR0 Rate = 1:64   WDT Rate = 1:32
BSF OPTION,0  BSF OPTION,1  BSF OPTION,2 TMR0 Rate = 1:256  WDT Rate = 1:128

BCF OPTION,PSA       BCF OPTION,3    Prescaler assigned to TMR0
BSF OPTION,PSA       BSF OPTION,3      Prescaler assigned to the WDT
BCF OPTION,T0SE      BCF OPTION,4    Increment on low-to-high on RA4/T0CKI pin 
BSF OPTION,T0SE      BSF OPTION,4    Increment on high-to-low on RA4/T0CKI pin 
BCF OPTION,T0CS      BCF OPTION,5    Internal Instruction cycle clock (CLKOUT) 
BSF OPTION,T0CS      BSF OPTION,5    Clock source select. Transition on  RA4/T0CKI Pin
BCF OPTION,INTEDG  BCF OPTION,6    Interrupt on falling edge of RB0/INT Pin 
BSF OPTION,INTEDG   BSF OPTION,6    Interrupt on rising edge of RB0/INT Pin  
BCF OPTION,RBPU     BCF OPTION,7    PORT B Pull-ups are enabled 
BSF OPTION,RBPU     BSF OPTION,7    PORT B Pull-ups are disabled   

STATUS address is either 03h or 83h - it is mapped at both locations.
BTFSS STATUS,C or  BTFSC 03,0  Test the carry bit.  C=1=set = carry occurred
BTFSS STATUS,C  or BTFSC 03,0  Test the carry bit.  C=0=reset = carry did not occur
BTFSS STATUS,DC  BTFSS 03,1  Test the digit carry bit.  C=1=set = carry-out from the 
        4th lower order bit of the result occurred.   
BTFSS STATUS,DC  BTFSS 03,1  Test the digit carry bit.  C=0=reset = carry-out did not
        occur from the 4th lower order bit of the result.
BTFSS STATUS,Z  or BTFSC 03,2  Test the zero bit.  Z=1=set = result of arithmetic 
     or logic operation is zero. 
BTFSS STATUS,Z  or BTFSC 03,2  Test the zero bit.  Z=0=reset = result of arithmetic 
     or logic operation is not zero. 
BSF STATUS,RP0  BSF 03,5    Go to Bank1 for TRISA or TRISB register
BCF STATUS,RP0  BCF 03,5    Go to Bank0 for programming

CLRF INDF,1  CLRF 00,1    Clear INDIRECT file 

RETFIE   Return from Interrupt    Sets INTCON,GIE

File name: File No: Comments:
equ 088h
equ 089h
equ 9
equ 8
equ 4
equ 0
equ 0Bh
equ 081h
equ 2
equ 5
equ 6
equ 3
equ 085h
equ 086h
;EEPROM Control Register 1
;EEPROM Control Register 2
;EEPROM address Register
;EEPROM Data Register
;File Select Register
;Interrupt and Timer bits
;Option Register
;Program Counter Low-bits
;Port A
;Port B
;Status Register
;Make Port A bits input or output
;Make Port B bits input or output
Bit name: Bit No: Comments and name of file holding the bit:
equ 0
equ 1
equ 4
equ 1
equ 7
equ 0
equ 5
equ 1
equ 5
equ 2
equ 0
equ 1
equ 2
equ 2
;Carry bit in Status file  C=0=no carry-out
;Digit Carry in Status DC=0=no carry out from 4th low-order digit
;In EECON1 EEIF=1=The write operation completed
;Place the result of the operation in the file
;Global Interrupt Enable bit. In INTCON  0=Disables all interrupts
;In EECON1  Read Control bit
;In Status. Register Bank select RP0=clear=bank0 RP0=set=bank1
;Store the result in the file
;In INTCON Timer0 Overflow Interrupt Enable bit
;In INTCON Timer0 Overflow Interrupt Flag bit
;Place the result in W
;In EECON1   Write Control bit
;In EECON1   EEPROM Write Enable bit
;Z in Status file.  Zero flag=set=1 when result of operation is zero!!