Difference between revisions of "PIC16F684"
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==Configuring I/O== |
==Configuring I/O== |
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This section shows two sections of code that are used for setting up the I/O of the PIC. The INIT_IO function sets up the ports by setting their default value and their direction. The second function, INIT_ADC sets up the A/D converter. |
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<pre> |
<pre> |
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INIT_IO |
INIT_IO |
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BCF STATUS,RP0 ;Bank 0 |
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BANK0 |
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CLRF PORTA ;Init PORTA - initially set to LOW |
CLRF PORTA ;Init PORTA - initially set to LOW |
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MOVLW B'000101' ;Set RA<0> as input |
MOVLW B'000101' ;Set RA<0> as input |
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MOVWF TRISA ; and set RA<5:1> |
MOVWF TRISA ; and set RA<5:1> |
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; as outputs |
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BANK1 |
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BSF STATUS,RP0 ;Bank 1 |
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CLRF PORTC ;Init PORTC - initially set to LOW |
CLRF PORTC ;Init PORTC - initially set to LOW |
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MOVLW B'000000' ;Set RC<5:0> as outputs |
MOVLW B'000000' ;Set RC<5:0> as outputs |
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MOVLW B'000001' |
MOVLW B'000001' |
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MOVWF ANSEL ;Set AN<0> (RA<0>) to Analog input |
MOVWF ANSEL ;Set AN<0> (RA<0>) to Analog input |
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; RA<5:1> remain digital I/O |
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RETURN |
RETURN |
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INIT_ADC |
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BCF STATUS,RP0 ;Bank 0 |
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MOVLW B'00000001' ; Set output to left justified |
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MOVWF ADCON0 ; Select AN<0> (RA<0>) as input |
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; Internal Vref |
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; Start ADC ON |
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BSF STATUS,RP0 ;Bank 1 |
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CLRF ADCON1 |
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MOVLW B'00100000' ;Set Clock TAD to 1.6us (Fosc/32) |
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MOVWF ADCON1 |
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RETURN |
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</pre> |
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''Notice that the two following bits of code are equivalent:'' |
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<pre> |
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CLRF PORTA |
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</pre> |
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and |
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<pre> |
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MOVLW B'000000' |
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MOVWF PORTA |
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</pre> |
</pre> |
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Revision as of 18:14, 11 July 2006
Overview
For a complete list of features, see this printout from the datasheet.
IMPORTANT: See PIC16F684 Registers for detailed information on registers.
Pinout
Label | Description |
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+ 5 V | |
Ground | |
External Voltage Reference | |
PORTA/PORTC Programmable I/O | |
A/D Channel | |
External Interrupt Input | |
PWM Output |
Initialization
Configuring I/O
This section shows two sections of code that are used for setting up the I/O of the PIC. The INIT_IO function sets up the ports by setting their default value and their direction. The second function, INIT_ADC sets up the A/D converter.
INIT_IO BCF STATUS,RP0 ;Bank 0 CLRF PORTA ;Init PORTA - initially set to LOW MOVLW B'000101' ;Set RA<0> as input MOVWF TRISA ; and set RA<5:1> ; as outputs BSF STATUS,RP0 ;Bank 1 CLRF PORTC ;Init PORTC - initially set to LOW MOVLW B'000000' ;Set RC<5:0> as outputs MOVWF TRISC CLRF ANSEL ;Set all pins initially to digital I/O MOVLW B'000001' MOVWF ANSEL ;Set AN<0> (RA<0>) to Analog input ; RA<5:1> remain digital I/O RETURN INIT_ADC BCF STATUS,RP0 ;Bank 0 MOVLW B'00000001' ; Set output to left justified MOVWF ADCON0 ; Select AN<0> (RA<0>) as input ; Internal Vref ; Start ADC ON BSF STATUS,RP0 ;Bank 1 CLRF ADCON1 MOVLW B'00100000' ;Set Clock TAD to 1.6us (Fosc/32) MOVWF ADCON1 RETURN
Notice that the two following bits of code are equivalent:
CLRF PORTA
and
MOVLW B'000000' MOVWF PORTA