HPWM in PIC basic pro 2.50a

[hell_pk]

Hi!
Has someone done HPWM using new pic basic pro 2.50a and used all channels in 18F4431 or 18F2431 series.I read somewhere you can use HPWM command for all channels.Is this so.....

[XZCV11]

Why dont you just implement the PWM that is embedded into the microcontroller.  you just need to write to the CCPxCON and CCPRxL register.  I hope this helps

[hell_pk]

Actually i want to use power PWM module of microcontroller for brushless DC motor control.

[eleckits]

there is a difference between PWM and HPWM.

the PWM instruction can be used with any pin of the micro and the HPWM can you be used just for the pin which is build in hardware.

[superkai]

Try this just adap it!!
http://www.micro-examples.com/public/microex-navig/doc/097-pwm-calculator.html

[spillaccio]

Hello.
Try this sample code and see the math formulas for calculate your frequency.

'****************************************************************
'*  Name    : HPWM.BAS                                          *
'*  Author  : [select VIEW...EDITOR OPTIONS]                    *
'*  Notice  : Copyright (c) 2008 [select VIEW...EDITOR OPTIONS] *
'*          : All Rights Reserved                               *
'*  Date    : 24/03/2008                                        *
'*  Version : 1.0                                               *
'*  Notes   :                                                   *
'*          :                                                   *
'****************************************************************
'*                    TESTED ON PIC16F877A                      *
'****************************************************************
define osc 20
TRISA=%00000000
TRISB=%00000000
TRISC=%00000000
ADCON1=7
'****************************************************************
'Frequency ( f ) and period ( P ) are inversely proportional. f = 1/P, & P = 1/f.
'
'To calculate the value to be loaded into PR2:
'(20MHz / (4 * TMR2 prescale value * 38KHz)) - 1= PR2.
'
'We'll use a prescale value of 1 for timer2.
'
'4 * 1 * 250,000 = 1,000,000
'20,000,000 / 1,000,000 = 20
'20 - 1 = 19
'
'We'll load 19 into PR2, and accept the minimal error.
'******************************************************************
'******************************************************************
' I randomly chose a duty cycle of 50% for this application. To setup the duty cycle, there are two registers that need to be configured.
'
' CCPRL1  contains the eight (most significant bits), and CCP1CON <4:5> (CCP1CON bits 4 and 5) contain the two (least significant bits).
'Since we will only have a maximum of 6-bits resolution, we only need to load the CCPR1 register. CCP1CON bits 4 & 5 will be loaded with 0's.
'
'To figure the value to load into CCPRL1 for 38KHz @ 20MHz with a 50% duty cycle:
'
'(PR2 + 1) * TMR2 prescale * 50% Duty Cycle = value for CCPRL1, or
'(19 + 1) * 1 * 0.50 = 26 * 0.50 = 5
'******************************************************************
' IF YOU WANT TURN OFF THE PWM MODE SET CCP1CON = %00000000
'******************************************************************

PR2 = 19 ' Set PWM Period for exactly 250KHz
CCPR1L = 5 ' Set PWM Duty-Cycle APPROX. to 50%  "IF NECESSARY CHANGE VALUE TO 10"
CCP1CON = %00001100 ' Mode select = PWM
T2CON = %00000100 ' Timer2 ON + 1:1 prescale ratio
TRISC.2 = 0 ' CCP1 to Output

MAIN:
'YOUR PROGRAM"
GoTo MAIN

Spillaccio

[nileshhande]

Hi, Could you please explain if i use 16f877a with 4mhz crystal then what all changes required in this code?
Thanks.