Multiple PWM pins

[HenrikOlsson]

Hi,
The 4520 has 2 CCP modules so you can get two PWM-outputs, ie two PWM-signals with the same frequency but different dutycycle. The reference to "one, two or four outputs" probably refers to using the ECCP module in half or full bridge mode. Then the PWM signal "comes out" on multiple pins but it's still "the same" signal - basically.

The 2331 also has 2 CCP modules plus the PCPWM-module with 3 PWM generators (the 4331 has 4) so all in all, using the 2331, you can get 5 PWM outputs. Note that the HPWM command does not work for PCPWM module in the 2331, you'll have to configure it "manually".

If you don't need the extended features of the PCPWM module (which, by the sound of it you don't) then perhaps something like the 25K22 might work, it's a lot cheaper then the 2331. There are loads and loads of 18F series parts with 3 or more (E)CCP modules. I'm not entirely sure if the HPWM command supports more than 2 channels though but it's easy enough to configure the registers manually.

/Henrik.

[Scampy]

There are loads and loads of 18F series parts with 3 or more (E)CCP modules. I'm not entirely sure if the HPWM command supports more than 2 channels though but it's easy enough to configure the registers manually.

/Henrik.

After doing hours of googling, I stumbled across this post on a forum http://www.sonsivri.to/forum/index.php?topic=24131.0

Looking through his sample code it has

'PIC16F767 Device Controlling Red/White/Blue LED's
'Written July 2, 2009
'Copyright (c) PilotPTK
'U1 Main LED Driver


DEFINE OSC 20
ADCON1 = %10001101	'Port A0,A1 Analog, VREF+ = VDD, Right Justified Result
CCP1CON = %00001100	'CCP Setup (PWM Mode)
CCP2CON = %00001100	'CCP Setup (PWM Mode)
CCP3CON = %00001100	'CCP Setup (PWM Mode)

And then later down

HPWM 1,0,5000
HPWM 2,0,5000
HPWM 3,0,5000

So on that basis I would assume PBP's HPWM command support more than two channels.... so now to look for a chip that's 5v (as 3.3v is not supported on my development board) and has four ECCP modules, and then see if I can port the working code on the 18f4520 to it