CCP2 troubles with 18F4620
I have successfully used this code with an 18F2221 and it worked fine, and as far as I can tell everything is configured to work with the 18F4620 but I can not get usable results from the CCP2 input. CCP1 works fine and I'm using the same configs and pulse on both pins. It successfully interrupts but the value returned is always 65,534 regardless of the pulse length. I'm sure I'm missing a config somewhere, but could use some help finding it.
Code:'**************************************************************** '* Version : 1.0 PIC18F4620 11/18/2015 (Works on 18F2221) * '* Notes : proto board 1 testing * '* : pulse input on CCP1 works fine * '* : pulse input on CCP2 does not work, shows 65,534 * '**************************************************************** OSCCON=%01110000 ' SET TO 8 MHZ internal oscillator DEFINE OSC 08 ' 8MHZ clock speed DEFINE INTHAND X_CCP_INT ' Declare interrupt handler ADCON1 = 15 ' All digital (AN0-AN3 will be used) CMCON = 7 ' Turns off comparators define LCD_COMMANDUS 1500 ' set command delay in us define LCD_DATAUS 50 ' set data delay in us define LCD_DREG PORTD ' set LCD data port define LCD_DBIT 4 ' set LCD starting data bit define LCD_RSREG PORTD ' define RS port define LCD_RSBIT 2 ' define RS bit define LCD_EREG PORTD ' set LCD ENABLE port define LCD_EBIT 3 ' set LCD ENABLE bit define LCD_BITS 4 ' set LCD bits 4 or 8 define LCD_LINES 2 ' set # of LCD rows 2 or 4 Symbol Capture = PIR1.2 ' CCP1 capture flag SYMBOL CapIE = PIE1.2 ' CCP1 interrupt enable bit SYMBOL CapPriEn = IPR1.2 ' priority enable bit for CCP1 interrupt SYMBOL PriEnable = RCON.7 ' set to enable priority levels on interrupts _T1 VAR WORD BANKA SYSTEM ' 1st capture value PW VAR WORD BANKA SYSTEM ' 2nd capture value & ultimately final pulse width CF VAR BYTE BANKA SYSTEM ' indicates when last capture is ready Period var word Symbol Capture2 = PIR2.0 ' CCP2 capture flag SYMBOL CapIE2 = PIE2.0 ' CCP2 interrupt enable bit SYMBOL CapPriEn2 = IPR2.0 ' priority enable bit for CCP2 interrupt _T2 VAR WORD BANKA SYSTEM ' 1st capture value PW2 VAR WORD BANKA SYSTEM ' 2nd capture value & ultimately final pulse width CF2 VAR BYTE BANKA SYSTEM ' indicates when last capture is ready Period2 var word pause 500 LCDOUT $FE,1 CLEAR ' clear RAM on POR TRISC.2 = 1 ' CCP1 input pin (Capture1 input on 18F4620) TRISC.1 = 1 ' CCP2 input pin (Capture2 input on 18F4620) INTCON = 0 ' Interrupts off for now GOTO start ' jump over interrupt handler ASM X_CCP_INT BTFSC PIR1,2 ; if ccp1 BRA CCP_INT ; goto CCP_INT BTFSC PIR2,0 ; if ccp2 BRA CCP2_INT ; goto CCP2_INT RETFIE FAST ; outta here CCP_INT BTFSS CCP1CON,0 ; capture from rising edge? BRA Fall ; no .. goto falling edge MOVFF CCPR1L, _T1 ; get low capture byte into _T1 MOVFF CCPR1H, _T1+1 ; get high capture byte into _T1 BRA IntExit ; outta here Fall MOVFF CCPR1L, PW ; get low capture byte into PW MOVFF CCPR1H, PW+1 ; get high capture byte into PW BSF CF,0 ; indicate last capture IntExit BTG CCP1CON,0 ; toggle between rising/falling edge captures BCF PIR1,2 ; clear capture interrupt flag bit RETFIE FAST ; return/restore W, STATUS and BSR CCP2_INT BTFSS CCP2CON,0 ; capture from rising edge? BRA Fall2 ; no .. goto falling edge MOVFF CCPR2L, _T2 ; get low capture byte into _T1 MOVFF CCPR2H, _T2+1 ; get high capture byte into _T1 BRA IntExit2 ; outta here Fall2 MOVFF CCPR2L, PW2 ; get low capture byte into PW MOVFF CCPR2H, PW2+1 ; get high capture byte into PW BSF CF2,0 ; indicate last capture IntExit2 BTG CCP2CON,0 ; toggle between rising/falling edge captures BCF PIR2,0 ; clear capture interrupt flag bit RETFIE FAST ; return/restore W, STATUS and BSR ENDASM start: '******************** CCP1 / CCP2 / Timer 1 ******************** CCP1CON = %00000110 'Capture mode, capture on 4th rising edge CCP2CON = %00000110 'Capture mode, capture on 4th rising edge T1CON.7=1 'Enable timer 16 bit ` T1CON.6=1 'Timer1 OSC T1CON.5=1 '1:8 prescaler T1CON.4=1 '1:8 prescaler T1CON.3=0 'Timer1 OSC off T1CON.2=0 'sychro clock T1CON.1=0 'Internal clock TMR1H = 0 'Clear high byte of TMR1 counter TMR1L = 0 'Clear low byte PriEnable = 1 'Enable priority levels on interrupts Capture = 0 'Clear capture flag bit Capture2 = 0 'Clear capture flag bit CapPriEn = 1 'Set CCP1 int to high priority CapPriEn2 = 1 'Set CCP2 int to high priority CapIE = 1 'Enable the CCP1 capture interrupt CapIE2 = 1 'Enable the CCP2 capture interrupt INTCON = %11000000 'Global + peripheral ints enabled T1CON.0 = 1 'Turn TMR1 on here main: IF CF.0 THEN period = PW-_T1 CF.0 = 0 ENDIF IF CF2.0 THEN period2 = PW2-_T2 CF2.0 = 0 ENDIF lcdout $fe, $80, "CCP1= ", dec5 period lcdout $fe, $C0, "CCP2= ", dec5 period2 goto main end
Bookmarks