Thank you for the reply mackrackit. What I'm actually doing is taking a 3 position knob say (slow, medium, and fast speed settings) I bring 2 of the settings into a dual opto on a pcb and basically turn it into an analog signal using a set of four resistors on the output. For example slow speed would give me a close to 0V on the pin of the PIC. Medium means niether opto is on and gives 2.5V to the PIC. Fast speed turns the bottom opto on giving close to 5V signal on the PIC. Analog Low I have defined as 256 decimal or 1.25V on the pin. Analog high I have defined as 768 or 3.75V. It's just a way I tried to use 3 digital input as one analog to save I/O ports. I hope this is a good explaination. If you would like to see the circuit I can share that as well.
I have done this PWM before but with much less code so I went back to the basics. Here is the code that I have running right now and does work correctly.
Code:
'-------------------------------------------------------------------------'
' PIC Defines Specific to PIC Basic Pro '
'-------------------------------------------------------------------------'
' 1. Use internal system clock
@ DEVICE PIC16F684, INTRC_OSC_NOCLKOUT
' 2. Turn watchdog timer on
@ DEVICE PIC16F684, WDT_OFF
' 3. Power on time on
@ DEVICE PIC16F684, PWRT_ON
' 4. Turning off the master clear input
@ DEVICE PIC16F684, MCLR_OFF
' 5. Brown out detect on
@ DEVICE PIC16F684, BOD_ON
' 6. Data EE Read protect is off
@ DEVICE PIC16F684, CPD_OFF
' 7. Code protect is off
@ DEVICE PIC16F684, PROTECT_OFF
'-------------------------------------------------------------------------'
' Hardware Defines Specific to PIC Basic Pro '
'-------------------------------------------------------------------------'
define ADC_BITS 10 'Set A/D coverter to use 10 bits
define ADC_SAMPLEUS 50 'Set A/D sample time as 50us
DEFINE OSC 8 'Change clock speed to 8Mhz
'-------------------------------------------------------------------------'
' Define Program Variables '
'-------------------------------------------------------------------------'
R VAR BYTE
ScaledX VAR BYTE
ScaledY VAR BYTE
ShortX VAR BYTE
ShortY VAR BYTE
Slope VAR WORD
AnalogLow VAR WORD 'Digital value for an analog low signal
AnalogHigh VAR WORD 'Digital value for an analog high signal
CurrentSpeed VAR WORD
DUTY VAR WORD
ExtLimit VAR WORD 'Stored value of the extend limit setting
JoyX VAR WORD
JoyY VAR WORD
RetLimit VAR WORD 'Stored value of the retract limit setting
Position VAR WORD 'Analog value of the internal potentiometer
Seeking VAR WORD
Speed VAR WORD
'-------------------------------------------------------------------------'
' Define I/O and EEPROM Definitions '
'-------------------------------------------------------------------------'
' The following 3 Data Commands write the Program Name and Revision
' number on the chips EEPROM in Location D0 - FF. This can be read
' by placing the chip in the programmer, reading it with MPLAB,
' and viewing the EEPROM.
DATA @208, "BadBoy Mowers "
DATA @224, "U3 Double "
DATA @240, "Rev. 1 A.S. "
data @0,word 768 'Set default extend limit
data @2,word 256 'Set default retract limit
AnalogHigh = 768 'Set analog high signal level
AnalogLow = 256 'Set analog low signal level
' READ 1, RetLimit.Highbyte
' READ 0, RetLimit.Lowbyte
' READ 3, ExtLimit.Highbyte
' READ 2, ExtLimit.Lowbyte
'-------------------------------------------------------------------------'
' Initialise PIC Hardware '
'-------------------------------------------------------------------------'
CMCON0 = 7 'Turn comparators off
ADCON0.7 = 1 'Set A/D Values to be right justified
ADCON0.0 = 1 'Turn on A/D Converter
ANSEL = %00110111 'Turn on select analog registers
TRISA = %00001111 'Turn on select register inputs
TRISC = %00111111 'Turn on select register inputs
PR2 = 249
CCP1CON = %11001100
CCPR1L = 0
PIR1.1 = 0
T2CON.0 = 0
T2CON.1 = 0
T2CON.2 = 1
WHILE (PIR1.1 = 0)
WEND;
TRISC = %00000011
'-------------------------------------------------------------------------'
' Start of Main Program '
'-------------------------------------------------------------------------'
Main:
ADCIN 5, Speed
Speed.lowbyte = ADRESL
Speed.highbyte = ADRESH
CCP1CON.4 = Speed.0
CCP1CON.5 = Speed.1
CCPR1L = Speed >> 2
GOTO Main
There are some useless variables in there because I commented most of the code out. I'm going to slowly try to incorperate the rest in now since I know this basic works. One thing I just noticed is that when I pull the pot wiper wire out of AN5 the DC goes back to 50%, not sure why but I will figure it out. Thanks again and I hope to here from you soon because this is driving me nuts. I know it's something simple.
EPWM control
yeah but usually those internal diode are just simply too slow...
1000uF/Amp here... maybe i'm wrong?
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