PIC16F628 Data (PIC16F628.pdf - 2.6MB)
PIC16F628A.INC
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SPECIAL PURPOSE REGISTERS

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'
_INTOSC_OSC_CLKOUT    EQU  H'3FFD'
_INTOSC_OSC_NOCLKOUT  EQU  H'3FFC'
_INTRC_OSC_CLKOUT     EQU  H'3FFD'
_INTRC_OSC_NOCLKOUT   EQU  H'3FFC'
_EXTCLK_OSC           EQU  H'3FEF'
_HS_OSC               EQU  H'3FEE'
_XT_OSC               EQU  H'3FED'
_LP_OSC               EQU  H'3FEC'

ADDITIONAL INSTRUCTIONS

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

e:g:
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