Bruce
- 25th January 2010, 20:41
This is a simple example for using the 18F2431 motion feedback modules capture hardware
to learn IR codes, and codes from RF encoders.
'************************************************* ***************
'* Name : CODE_LEARN.BAS *
'* Author : B. Reynolds *
'* Notice : Copyright (c) 2008 B. Reynolds *
'* : All Rights Reserved *
'* Date : 8/22/2008 *
'* Version : 1.0 *
'* Notes : Using the 18F2431 Motion Feedback Module capture *
'* : to learn encoder or IR transmitter codes. *
'************************************************* ***************
' Connections;
' IR detector output to PORTA.2 CAP1 input
' PORTB.0 ------/\/\/\/----|>|----GND LED on RB0 (for press/release indicator)
' PORTC.6 --MAX232---PC serial port RX (to print results)
DEFINE NO_CLRWDT 1 ' it's disabled in config
DEFINE LOADER_USED 1
DEFINE OSC 4
DEFINE DEBUG_REG PORTC
DEFINE DEBUG_BIT 6
DEFINE DEBUG_BAUD 9600
DEFINE DEBUG_MODE 0 ' 1 = inverted, 0 = true
NumPulses CON 26 ' total signal states to learn (26 for Sony)
T1 VAR WORD[NumPulses]
INDEX VAR BYTE
KeyNum VAR BYTE
SYMBOL Capture = PIR3.1
CLEAR
ANSEL0 = 0 ' all digital
TRISA.2 = 1 ' cap1 input pin (Capture input)
INTCON = 0 ' interrupts off
TMR5H = 0 ' clear high byte of TMR5 count
TMR5L = 0 ' clear low byte
T5CON = %00000001 ' prescale=1:1, int clock, TMR5=on
Main:
CAP1CON = %01001000 ' auto time base reset, capture on every state change
Capture = 0
FOR KeyNum = 0 TO 14 ' learn 15 total button codes
CAP1CON = %01001000 '
HIGH 0 ' indicate start (user press button)
Capture = 0 ' clear capture flag before starting
' Wait for 1st capture on state-change. Note: We don't care what the 1st capture
' value is since it's the beginning high-to-low edge (for IR), and of no significance.
' We only want the length of each high & low signal after the falling edge.
WHILE Capture = 0 : WEND
Capture = 0
FOR INDEX = 0 TO NumPulses-1 ' captures IR signal in 1uS increments
WHILE Capture = 0 : WEND ' wait for capture event
Capture = 0 ' clear int flag after each capture
T1[INDEX] = ((CAP1BUFH<<8) + CAP1BUFL) ' store capture values
Next INDEX
CAP1CON = 0 ' disable capture immediately after to avoid unwanted captures
Capture = 0
' if user holds transmitter button down too long.
LOW 0 ' indicates user should release transmitter button
PAUSE 1000
' print button codes
FOR INDEX = 0 TO NumPulses-1 STEP 2
DEBUG "low = ", DEC T1[INDEX],"uS",13,10 ' print low signal period
DEBUG "high = ",DEC T1[INDEX+1],"uS",13,10 ' print high signal period
NEXT INDEX
DEBUG 10,13
NEXT KeyNum
Finished: ' indicate finished
TOGGLE 0
PAUSE 200
GOTO Finished
END
This capture module can capture the value of TMR5 on every state change, making
it really simple to capture & recreate timing signals for remote control encoders.
It's really handy if you don't have an O-scope, and want to create code for a custom IR or
RF encoder IC.
to learn IR codes, and codes from RF encoders.
'************************************************* ***************
'* Name : CODE_LEARN.BAS *
'* Author : B. Reynolds *
'* Notice : Copyright (c) 2008 B. Reynolds *
'* : All Rights Reserved *
'* Date : 8/22/2008 *
'* Version : 1.0 *
'* Notes : Using the 18F2431 Motion Feedback Module capture *
'* : to learn encoder or IR transmitter codes. *
'************************************************* ***************
' Connections;
' IR detector output to PORTA.2 CAP1 input
' PORTB.0 ------/\/\/\/----|>|----GND LED on RB0 (for press/release indicator)
' PORTC.6 --MAX232---PC serial port RX (to print results)
DEFINE NO_CLRWDT 1 ' it's disabled in config
DEFINE LOADER_USED 1
DEFINE OSC 4
DEFINE DEBUG_REG PORTC
DEFINE DEBUG_BIT 6
DEFINE DEBUG_BAUD 9600
DEFINE DEBUG_MODE 0 ' 1 = inverted, 0 = true
NumPulses CON 26 ' total signal states to learn (26 for Sony)
T1 VAR WORD[NumPulses]
INDEX VAR BYTE
KeyNum VAR BYTE
SYMBOL Capture = PIR3.1
CLEAR
ANSEL0 = 0 ' all digital
TRISA.2 = 1 ' cap1 input pin (Capture input)
INTCON = 0 ' interrupts off
TMR5H = 0 ' clear high byte of TMR5 count
TMR5L = 0 ' clear low byte
T5CON = %00000001 ' prescale=1:1, int clock, TMR5=on
Main:
CAP1CON = %01001000 ' auto time base reset, capture on every state change
Capture = 0
FOR KeyNum = 0 TO 14 ' learn 15 total button codes
CAP1CON = %01001000 '
HIGH 0 ' indicate start (user press button)
Capture = 0 ' clear capture flag before starting
' Wait for 1st capture on state-change. Note: We don't care what the 1st capture
' value is since it's the beginning high-to-low edge (for IR), and of no significance.
' We only want the length of each high & low signal after the falling edge.
WHILE Capture = 0 : WEND
Capture = 0
FOR INDEX = 0 TO NumPulses-1 ' captures IR signal in 1uS increments
WHILE Capture = 0 : WEND ' wait for capture event
Capture = 0 ' clear int flag after each capture
T1[INDEX] = ((CAP1BUFH<<8) + CAP1BUFL) ' store capture values
Next INDEX
CAP1CON = 0 ' disable capture immediately after to avoid unwanted captures
Capture = 0
' if user holds transmitter button down too long.
LOW 0 ' indicates user should release transmitter button
PAUSE 1000
' print button codes
FOR INDEX = 0 TO NumPulses-1 STEP 2
DEBUG "low = ", DEC T1[INDEX],"uS",13,10 ' print low signal period
DEBUG "high = ",DEC T1[INDEX+1],"uS",13,10 ' print high signal period
NEXT INDEX
DEBUG 10,13
NEXT KeyNum
Finished: ' indicate finished
TOGGLE 0
PAUSE 200
GOTO Finished
END
This capture module can capture the value of TMR5 on every state change, making
it really simple to capture & recreate timing signals for remote control encoders.
It's really handy if you don't have an O-scope, and want to create code for a custom IR or
RF encoder IC.