PIC16F684 - Revision history

Stephens: /* Setting Up for PWM Output */

2006-07-11T23:25:48Z

Setting Up for PWM Output

← Older revision		Revision as of 18:25, 11 July 2006
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	==Setting Up for PWM Output==		==Setting Up for PWM Output==

			Using the built-in PWM functionality is very useful, but it a little tricky to setup and use. First, you need to initialize the PWM by setting the mode, initial duty cycle, and frequency:
			<pre>
			INIT_PWM
			BCF STATUS,RP0 ;Bank 0
			MOVLW B'10001100' ;Half-Bridge Output, Dual-Mode PWM
			MOVWF CCP1CON
			MOVLW B'00000100' ;Timer2 enabled with prescale 1
			MOVWF T2CON
			MOVLW B'01111111' ;50% duty cycle
			MOVWF CCPR1L

			BSF STATUS,RP0 ;Bank 1
			MOVLW 0xFF
			MOVWF PR2 ;Set frequency to 19.53 kHz

			RETURN
			</pre>

			Next is setting the desired duty cycle. A 0% duty cycle will correspond to 5v on P1A and 0v on P1B. A 100% duty cycle will correspond to the opposite, 0v on P1A and 5v on P1B. The duty cycle is a 10-bit number that spans two registers, CCPR1L<7:0> and CCP1CON<5:4>. To set a 100% duty cycle, you will need code like this:

			<pre>
			UPDATE_PWM
			BCF STATUS,RP0 ;Bank 0
			MOVLW B'11111111' ; Set 8 MSbs to the CCPR1L register
			MOVWF CCPR1L
			BSF CCP1CON,5 ; set 2 LSbs to 1
			BSF CCP1CON,4
			</pre>

2006-07-11T23:15:01Z

Configuring I/O

2006-07-11T23:14:00Z

Configuring I/O

@@ Line 33: / Line 33: @@
 ==Configuring I/O==
 <pre>
 INIT_IO
 	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
+						;	as outputs
 	CLRF 		PORTC 			;Init PORTC - initially set to LOW
 	MOVLW 	B'000000'			;Set RC<5:0> as outputs
@@ Line 48: / Line 50: @@
 	MOVLW	B'000001'
 	MOVWF		ANSEL			;Set AN<0> (RA<0>) to Analog input
-								;	RA<5:1> remain digital I/O
+						;	RA<5:1> remain digital I/O
 	RETURN
 </pre>

2006-07-11T22:52:56Z

Configuring I/O

← Older revision		Revision as of 17:52, 11 July 2006
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	==Configuring I/O==		==Configuring I/O==

			<pre>
			INIT_IO
			BANK0
			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
			BANK1
			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
			</pre>

	==Setting Up for PWM Output==		==Setting Up for PWM Output==

2006-07-10T23:31:17Z

Overview

← Older revision		Revision as of 18:31, 10 July 2006
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	For a complete list of features, see [[media:pic16f684 features.png\|this printout]] from the datasheet.		For a complete list of features, see [[media:pic16f684 features.png\|this printout]] from the datasheet.

		⚫	IMPORTANT: '''See [[PIC16F684 Registers]] for detailed information on registers.'''

	===Pinout===		===Pinout===
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	\| <math>P1A/B/C/D\,</math> \|\| PWM Output		\| <math>P1A/B/C/D\,</math> \|\| PWM Output
	\|}		\|}


⚫	IMPORTANT: '''See [[PIC16F684 Registers]] for detailed information on registers.'''

	==Initialization==		==Initialization==

2006-07-10T23:30:55Z

← Older revision		Revision as of 18:30, 10 July 2006
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	\|}		\|}

	==Configuration==

	'''See [[PIC16F684 Registers]] for detailed information on registers.'''		IMPORTANT: '''See [[PIC16F684 Registers]] for detailed information on registers.'''

			==Initialization==

2006-07-10T23:29:44Z

← Older revision		Revision as of 18:29, 10 July 2006
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	\|}		\|}

	==~~Registers~~==		==Configuration==

	See [[PIC16F684 Registers]] for ~~more~~ detailed information.		'''See [[PIC16F684 Registers]] for detailed information on registers.'''

	===Important Registers===

	{\|
	! width="100"\| Register Name !! width="400"\| What it Does
	\|}

	==Configuring I/O==		==Configuring I/O==

2006-07-10T21:49:33Z

Registers

← Older revision		Revision as of 16:49, 10 July 2006
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	==Registers==		==Registers==

			See [[PIC16F684 Registers]] for more detailed information.

			===Important Registers===

			{\|
			! width="100"\| Register Name !! width="400"\| What it Does
			\|}

	==Configuring I/O==		==Configuring I/O==

2006-07-06T17:11:33Z

Pinout

← Older revision		Revision as of 12:11, 6 July 2006
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	\| <math>V_{SS}\,</math> \|\| Ground		\| <math>V_{SS}\,</math> \|\| Ground
	\|-		\|-
	\| <math>V_{~~ref~~}\,</math> \|\| External Voltage Reference		\| <math>V_{REF}\,</math> \|\| External Voltage Reference
	\|-		\|-
	\| <math>RA\#/RC\#\,</math> \|\| PORTA/PORTC Programmable I/O		\| <math>RA\#/RC\#\,</math> \|\| PORTA/PORTC Programmable I/O

2006-07-06T17:11:21Z

Pinout

← Older revision		Revision as of 12:11, 6 July 2006
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	\|-		\|-
	\| <math>V_{ref}\,</math> \|\| External Voltage Reference		\| <math>V_{ref}\,</math> \|\| External Voltage Reference
			\|-
	\| <math>RA\#/RC\#\,</math> \|\| PORTA/PORTC Programmable I/O		\| <math>RA\#/RC\#\,</math> \|\| PORTA/PORTC Programmable I/O
	\|-		\|-