using the pwm's in pic18f2431-2331-4331-4431

[luminas]

Read Darrel comment above.
You have to setup manually, or you can use 2 CCP HPWM only with PBP

[Darrel Taylor]

On these chips, I defer to Bruce's experience. (See post #4)

Bruce,

Is there really 2 normal CCP's and 4 other PWM's on these chips? Total of 6?
Or am I looking at the datasheet wrong?
The GIF image in post #4 shows 6 traces, but the program doesn't ues CCPCON?.

Haven't used one yet.
<br>

[Bruce]

DT,

The 28-pin version has 6 power control pwm outputs, and 2 standard CCP pwm outputs
for a total of 8. The 40-pin has 8 power control pwm outputs and the 2 standard CCP.

The only thing I don't like is they use the CCP1 & CCP2 pwm outputs as power control
pwm fault inputs.

You should grab a couple samples. The motion feedback module on these is awesome.

[Darrel Taylor]

WOW, that's a tough read.

But after a few hrs in the datasheet. Yeah, these are cool.

Got the (IC) Input Capture block: Very cool.
The (QEI) Quadrature Encoder Interface: OK sorta cool.
And up to 4 14-bit PWM's. (4 additional complimentary outputs) Not usable with CCP's at the same time.
Not as cool as I expected.

Still worth further investigation.
Samples on order. Thanks Bruce.
<br>

[rmteo]

How about a 28-pin PIC24FJxxGA002. 5 independent input capture AND 5 independent PWM's/OC (up to 16-bit resolution and 500kHZ). About $2 each (depending on flash from 16-64kB, 4kB or 8kB RAM). Plus lots of other stuff like 2 UART's, built-in RTCC, 2 SPI, 2 I2C, etc. Plus you can select which pins you want to use for most of the peripherals.

[mystified]

Thanks did not know that ccp and pwm0-5 are not the same pins that helped now how about setuo for timer 2.

[Bruce]

If you're using HPWM you don't need to mess with Timer2. It's automatically handled
for you.

If you plan to setup hardware PWM manually, these calcs should help.

PR2=(Fosc/(4*PS*Freq))-1
TMR2 Prescaler = 1 PR2 = (8MHz/(4*1*12,000)) = (8MHz/48,000)-1 PR2 = 165.666
TMR2 Prescaler = 4 PR2 = (8MHz/(4*4*12,000)) = (8MHz/192,000)-1 PR2 = 40.666
TMR2 Prescaler = 16 PR2 = (8MHz/(4*16*12,000))-1 = (8MHz/768,000))-1 PR2 = 9.416

CCPR1L:CCP1CON<5:4>=(PR2+1)*4*Duty%
(165+1)*4*0.5 = 332
(40+1)*4*0.5 = 82
(9+1)*4*0.5 = 20

To load the duty cycle registers just place the value calculated in a word, and
do something like this;

Duty = 332              ' Roughly 50% duty cycle
CCP1CON.4 = Duty.0	' Setup 10-bit duty cycle as
CCP1CON.5 = Duty.1	' a 10-bit word
CCPR1L = Duty >> 2

Search here for HPWM and you'll find a boat-load more examples.