16F1828 HPWM and ADC

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- 16th November 2015, 20:11
midali

16F1828 HPWM and ADC

Hi guys,
I have a strange problem with 16F1828 .
So, I want to use AN6 (PORTC.2) to read a variable from 5k potentiometer . In main program if I use only HPWM2 , all works ok.
If I add HPWM1 , on AN6 pin I have not a proportional voltage, like this pin is not analog input.

Can somebody help me, please ? The last 2 days I spent my time to solve this problem, but no succes !

Code:

#CONFIG __CONFIG _CONFIG1, _FCMEN_OFF & _FOSC_INTOSC & _WDTE_OFF & _MCLRE_OFF & _CP_ON & _IESO_OFF & _BOREN_OFF & _PWRTE_OFF __CONFIG _CONFIG2, _PLLEN_OFF & _STVREN_OFF & _LVP_OFF #ENDCONFIG DEfine OSC 4 OSCCON = %01101010 'sets the internal oscillator to 4Mhz ADCON0 = %00000000 ADCON1 = %00000000 FVRCON = %11000010 'voltage reference set to 2.048V CM1CON0 = 0 ' COMPARATORS OFF CM1CON1 = 0 CM2CON0 = 0 ' COMPARATORS OFF CM2CON1 = 0 CPSCON0 = 0 'CAPACTIVE SENSE MODULE OFF RCSTA.7 = 0 'SERIAL PORT OFF 'APFCON0 = %10000000 'APFCON1 = %00001010 'APFCON1.3 = 1 TRISA = %00000011 TRISB = %00000000 TRISC = %00000100 ' PORTC.2 input ANSELA = %00000011 ANSELB = %00000000 ANSELC = %00000100 ' ANALOG INPUT AN6 OPTION_REG.7 = 1 ' disable WPU WPUA = %00000000 WPUB = %00000000 WPUC = %00000000 porta = 0 portb = 0 portc = 0 inh1 var portc.4 inh2 var portc.0 adval var byte duty1 var byte duty2 var byte duty1 = 0 pause 200 '========================PROGRAM============================= main: adcin 6 , adval pause 10 duty2 = adval hpwm 2 , duty2, 2000 hpwm 1 , duty1, 2000 '- here is problem high inh1 high inh2 goto main end '=============================================================

1000 x thx
- 17th November 2015, 07:41
midali

Re: 16F1828 HPWM and ADC

..or a simple way to see where is the problem (PORTC.2 is not set ADC) !

Datasheet 16F1828
http://ww1.microchip.com/downloads/e.../40001419F.pdf

Code:

#CONFIG __CONFIG _CONFIG1, _FCMEN_OFF & _FOSC_INTOSC & _WDTE_OFF & _MCLRE_OFF & _CP_ON & _IESO_OFF & _BOREN_OFF & _PWRTE_OFF __CONFIG _CONFIG2, _PLLEN_OFF & _STVREN_OFF & _LVP_OFF #ENDCONFIG DEfine OSC 4 OSCCON = %01101010 'sets the internal oscillator to 4Mhz ADCON0 = %00000000 ADCON1 = %00000000 FVRCON = %11000010 'voltage reference set to 2.048V CM1CON0 = 0 ' COMPARATORS OFF CM1CON1 = 0 CM2CON0 = 0 ' COMPARATORS OFF CM2CON1 = 0 CPSCON0 = 0 'CAPACTIVE SENSE MODULE OFF RCSTA.7 = 0 'SERIAL PORT OFF 'APFCON0 = %10000000 'APFCON1 = %00001010 'APFCON1.3 = 1 TRISA = %00000011 TRISB = %00000000 TRISC = %00000100 ' PORTC.2 input ANSELA = %00000011 ANSELB = %00000000 ANSELC = %00000100 ' ANALOG INPUT AN6 OPTION_REG.7 = 1 ' disable WPU WPUA = %00000000 WPUB = %00000000 WPUC = %00000000 porta = 0 portb = 0 portc = 0 inh1 var portc.4 inh2 var portc.0 adval var byte duty1 var byte duty2 var byte duty1 = 0 pause 200 '========================PROGRAM============================= main: adcin 6 , adval ' AN6(PORTC.2) is not ADC ? pause 10 duty1 = adval hpwm 1 , duty1, 2000 high inh1 high inh2 goto main end '=============================================================
- 17th November 2015, 08:04
richard

Re: 16F1828 HPWM and ADC

which thing doesn't work

no output on cp1 (portc.5) ?
or
adcin 6 yields an incorrect result ?

can I suggest try
duty1 = 128
hpwm 1 , duty1, 2000

is there an output ?

and

adcin 6, adval

debug #adval

is there a realistic result ?
- 17th November 2015, 08:23
midali

Re: 16F1828 HPWM and ADC

HPWM 1, 128, 1000 - I have a output
ADCIN 6 give me a incorrect result.

If I use ADCIN 6 with any HPWM (2,3,4) , I have correct ADC input, also correct PWM output.
- 17th November 2015, 08:37
midali

Re: 16F1828 HPWM and ADC

This code work perfectly :

Code:

main: adcin 6 , adval pause 10 duty1 = adval hpwm 2 , duty1, 2000 high inh1 high inh2 goto main end
- 17th November 2015, 08:53
midali

Re: 16F1828 HPWM and ADC

If I add HPWM1 line, I have not correct ADC input

Here AN6 pin is not ADC input:

Code:

main: adcin 6 , adval pause 10 duty1 = adval hpwm 2 , duty1, 2000 hpwm 1 , 128, 2000 high inh1 high inh2 goto main end
- 17th November 2015, 08:54
richard

Re: 16F1828 HPWM and ADC

try setting the pwm manually (the frequency will be way off ) but its worth a try

Code:

t2con=4 PR2 = 255 CCPR1L = adval ;set pwm ccp1con=12

I don't have a 16f1828 to test with , I do not think your code is incorrect but at this stage that's all I can offer
- 17th November 2015, 09:01
richard

Re: 16F1828 HPWM and ADC

just noticed you have no adc defines

Quote:

DEFINE ADC_BITS 8
DEFINE ADC_CLOCK 3
DEFINE ADC_SAMPLEUS 100

could help, they should be included anyway
- 17th November 2015, 09:18
richard

Re: 16F1828 HPWM and ADC

Quote:

ADCON1 = %00000000
FVRCON = %11000010 'voltage reference set to 2.048V

you are setting the frv (ps bit 6 of fvrcon is read only) but never connecting it to the adc module .
to use the fvr as ref you need to set adcon1 bits 0 & 1 to 1

you have also selected a conversion clock of fosc/2 which @4mhz is out of specs
you need fosc/4 or rc clock for adc
- 17th November 2015, 09:40
midali

Re: 16F1828 HPWM and ADC

Thank you very much for your help ,Richard !
I made the changes, but now CCPR1L = 0

Code:

Define OSC 4 OSCCON = %01101010 'sets the internal oscillator to 4Mhz DEFINE ADC_BITS 8 DEFINE ADC_CLOCK 3 DEFINE ADC_SAMPLEUS 100 ADCON0 = %00000000 ADCON1 = %00000011 FVRCON = %10000010 'voltage reference set to 2.048V CM1CON0 = 0 ' COMPARATORS OFF CM1CON1 = 0 CM2CON0 = 0 ' COMPARATORS OFF CM2CON1 = 0 CPSCON0 = 0 'CAPACTIVE SENSE MODULE OFF RCSTA.7 = 0 'SERIAL PORT OFF 'APFCON0 = %10000000 'APFCON1 = %00001010 'APFCON1.3 = 1 TRISA = %00000011 TRISB = %00000000 TRISC = %00000100 ' PORTC.2 input ANSELA = %00000011 ANSELB = %00000000 ANSELC = %00000100 ' ANALOG INPUT AN6 OPTION_REG.7 = 1 ' disable WPU WPUA = %00000000 WPUB = %00000000 WPUC = %00000000 porta = 0 portb = 0 portc = 0 inh1 var portc.4 inh2 var portc.0 adval var byte duty1 var byte duty2 var byte duty1 = 0 t2con=4 PR2 = 255 ccp1con=16 pause 200 '========================PROGRAM============================= main: adcin 6 , adval pause 10 CCPR1L = adval ;set pwm duty1 = adval hpwm 2 , duty1, 2000 high inh1 high inh2 goto main end '=============================================================
- 17th November 2015, 09:47
richard

Re: 16F1828 HPWM and ADC

ccp1con=16 is incorrect, that is just nothing

ccp1con=12 ; pwm mode

Quote:

I made the changes, but now CCPR1L = 0

?

CCPR1L = adval ;set pwm

if adval= 0 then yes it would
- 17th November 2015, 09:51
richard

Re: 16F1828 HPWM and ADC

Quote:

DEFINE ADC_BITS 8
DEFINE ADC_CLOCK 3
DEFINE ADC_SAMPLEUS 100

ADCON0 = %00000000
ADCON1 = %00000011

ADCON1 = %00000011 ; this line just destroyed all your defines

ADCON1 = ADCON1 | %00000011 ; will set bits 0 and 1 without wrecking the others
- 17th November 2015, 10:32
midali

Re: 16F1828 HPWM and ADC

Thx Richard, now I understand.

Now, AN6 work corectly. The value of CCPR1L is 2 x adval. If I divide adval to 2 , exist a little diference betwen PWM1 and PWM2 on outputs (~ 0,8 units)

Code:

t2con=4 PR2 = 255 ccp1con=12 pause 200 '========================PROGRAM============================= main: adcin 6 , adval pause 10 CCPR1L = adval/2 ;set pwm duty1 = adval hpwm 2 , duty1, 2000 high inh1 high inh2 goto main end '=============================================================
- 17th November 2015, 20:52
richard

Re: 16F1828 HPWM and ADC

some more things to consider

1.

Quote:

Many devices allow a selection of Timer resource for some or all of the PWM
channels. The HPWM command will automatically determine the preset Timer
selection upon execution. Note that PWM channels that share a single timer may
not operate at independent output frequencies. While duty-cycle settings are
always independent from one channel to the next, independent frequency settings
require independent timer resources.

you have not set any individual timer resource options [ CCPTMRS0 ]
so

Quote:

t2con=4
PR2 = 255

settings get overwritten by use of

Quote:

hpwm 2 , duty1, 2000

2.
you have not specified how your "pot" is connected , if its connected between vdd an ground then use of a fvr of 2.048 v is totally inappropriate and
may even damage your chip. analogue in voltage should never exceed vref

3.
all your trouble was probably caused by incorrect adc settings , hpwm1 should now work
- 18th November 2015, 08:41
midali

Re: 16F1828 HPWM and ADC

My potentiometer is connect between +5v and gnd.

I can not understood why I had some troubles because :

1. I used AN0 or AN1 and HPWM(1-4) worked perfectly

2. I used AN6 , so HPWM2 worked perfectly(AN6 analog input ok) ! , but when I added HPWM1 , the HPWM2 not worked because I had not a analog input. I suposed that exist a conflict between AN6 and HPWM1.

Now, HPWM1 work . AN6 work but here is some trouble, I have analog input but after some time toggle itself on digital input !
Now I read carefully in datasheet and I'll post the code.

Its clear that I'm begginer in pbp, all my projects are for hobby. Richard, you explained me step by step and I start to understand some "secrets" about settings. Thank you very much for patience!!
- 18th November 2015, 20:41
midali

Re: 16F1828 HPWM and ADC

I'm very confused.

I think that settings are ok, but some its very strange. I changed the PIC with another one, but the same results.

PIC config & settings :

Code:

OSCCON = %01101010 'sets the internal oscillator to 4Mhz DEFINE ADC_BITS 8 DEFINE ADC_CLOCK 3 DEFINE ADC_SAMPLEUS 100 ADCON0 = %00000000 ADCON1 = %00000000 FVRCON = %00000000 CM1CON0 = 0 ' COMPARATORS OFF CM1CON1 = 0 CM2CON0 = 0 ' COMPARATORS OFF CM2CON1 = 0 CPSCON0 = 0 'CAPACTIVE SENSE MODULE OFF RCSTA.7 = 0 'SERIAL PORT OFF TRISA = %00000011 'PORTA.0 and PORTA.1 set Input TRISB = %00000000 TRISC = %10000100 ' PORTC.7 and PORTC.2 input ANSELA = %00000011 ' AN0 and AN1 set analog ANSELB = %00000000 ANSELC = %00000100 ' AN6 set analog OPTION_REG.7 = %00000001 'WPU enable ; Fosc/4; Prescaler 1/4 WPUA = %00000000 WPUB = %00000000 WPUC = %10000000 ' enable WPUC.7 porta = 0 portb = 0 portc = 0 inh1 var portc.4 inh2 var portc.0 adval var byte duty1 var byte

Here work all 4 HPWM:

Code:

main: adcin 0 , adval '(or adcin 1 , adval) pause 10 duty1 = adval hpwm 1 , duty1, 2000 hpwm 2 , duty1, 2000 hpwm 3 , duty1, 2000 hpwm 4 , duty1, 2000 goto main end

Here works fine HPWM(2,3,4):

Code:

main: adcin 6 , adval pause 10 duty1 = adval hpwm 2 , duty1, 2000 hpwm 3 , duty1, 2000 hpwm 4 , duty1, 2000 goto main end

Here AN6 toggled to digital input (why ??):

Code:

main: adcin 6 , adval pause 10 duty1 = adval hpwm 1 , duty1, 2000 hpwm 2 , duty1, 2000 hpwm 3 , duty1, 2000 hpwm 4 , duty1, 2000 goto main end

I tried to set manually all 4 CCP , frequency doesn't matter (2-4khz is enough for me) , maxim duty cycle measured with a osciloscope is 99,7 % . What is very strange , after some time, the AN6 toggle from analog to digital input. I hope that manual settings are ok.

Code:

T2CON = %00000100 ' Timer2 ON PR2 = 255 CCP1CON = %00001100 CCP2CON = %00001100 CCP3CON = %00001100 CCP4CON = %00001100 pause 200 '========================PROGRAM============================= main: adcin 6 , adval pause 10 CCPR1L = adval CCPR2L = adval CCPR3L = adval CCPR4L = adval goto main end

So, If I add HPWM1 in main program , AN6 toggle instantly from analog input to digital input. If I set manual CCP , AN6 toggle from analog to digital after some time.

I tried with 16F1938 , the same program, with different analog inputs and all work ok.
- 18th November 2015, 21:06
richard

Re: 16F1828 HPWM and ADC

this might be the issue
http://ww1.microchip.com/downloads/e...Doc/80510C.pdf
- 21st November 2015, 09:10
Acetronics2

Re: 16F1828 HPWM and ADC

Hi, Midali

I do not see much config lines for your CCP Modules ...

Code:

'APFCON0 = %10000000 'APFCON1 = %00001010 'APFCON1.3 = 1

being commented out ... ( I did not check if correct )

as AN6 is shared by the CCP outputs and your ADC input ...

unfortunately, I do not have those 16F18xx chips here to verify.

did you try with another ADC input ( not CCPx related ), AN10 or 11 i.e. ???

Alain
- 21st November 2015, 11:41
midali

Re: 16F1828 HPWM and ADC

First time when I used HPWM ,I configured the APFCON to "APFCON1.3 = 1" but no succes.

Now I set manually the CCP and APFCON1.3 = 1, all its ok! AN6 work perfectly ! I want to play with it more time because I want to be sure that all its ok.
Also, I tried again with HPWM and some APFCON configs, but the same problems : AN6 is digital input or AN6 toggle from analog to digital input.

I'll try to test with AN10 or An11 , but will be a little hard because my pcb is make ready .

Thank you very much Alain...
- 21st November 2015, 14:50
midali

Re: 16F1828 HPWM and ADC

Conclusions :

1. I tested with AN10 and ADC work perfectly with HPWM. Also, works well with AN0 and AN1.(another ADC I not tested)
2. ADC on AN6 pin work perfectly if I config APFCON1.3 = 1 and manually set for CCP.
3. I think that all troubles was from PIC revision...may be I'm wrong
4. I'll modify my PCB and I'll use AN10 ( this pin is near AN6)
5. In my opinion , is the best if avoid to use PORTC.2 (AN6) .
6. I prefer to work with HPWM because I can set very easy the freq and duty cycle .

Thank you again to Richard and Alain for your help!