flow rate

How to interface LPC2106 with L293D

make use of any two available gpios.

are u using PWM in IRQ maode??

Hi every body

I required some programming help. I am using LPC2106 for my project
Can you provide one example program for generation of 60% duty cycle PWM wave using keil ‘c’?
How to configure the PWM registers, how to find out match register value
I am using 14.7C61Mhz crystal & not using PLL

Thank you

Regards

chandu

[Thread moved to ARM Development]

hope u have a fair understanding of timers in LPC21xx controllers.. it is important for the PWM to be produced..

here take a look of this sample code based on 214x controller hope it helps ..

#include "LPC214x.h"                        /* LPC21xx definitions */
#include "type.h"
#include "irq.h"
#include "timer.h"
#include "pwm.h"

volatile DWORD match_counter;

/******************************************************************************
** Function name:		PWMHandler
**
** Descriptions:		PWM interrupt handler
**				For now, it only deals with PWM match 0
**
** parameters:			None
** Returned value:		None
** 
******************************************************************************/
// mthomas: +static
static void PWMHandler (void) __irq 
{
    DWORD regVal;

    regVal = PWMIR;
    IENABLE;			/* handles nested interrupt */
    if ( regVal & MR0_INT )
    {
	match_counter++;	
    }
    PWMIR |= regVal;		/* clear interrupt flag on match 0 */
    IDISABLE;
    VICVectAddr = 0;		/* Acknowledge Interrupt */
}

/******************************************************************************
** Function name:		PWM_Init
**
** Descriptions:		PWM initialization, setup all GPIOs to PWM0~6,
**				reset counter, all latches are enabled, interrupt
**				on PWMMR0, install PWM interrupt to the VIC table.
**
** parameters:			Duty cycle
** Returned value:		true or fase, if VIC table is full, return false
** 
******************************************************************************/
DWORD PWM_Init( DWORD cycle )
{
    match_counter = 0;
    PINSEL0 = 0x000A800A;	/* set GPIOs for all PWMs */
    PINSEL1 = 0x00000400;

    PWMTCR = TCR_RESET;		/* Counter Reset */ 
		
    PWMPR = 0x00;		/* count frequency:Fpclk */
    PWMMCR = PWMMR0I | PWMMR0R;	/* interrupt on PWMMR0, reset on PWMMR0, reset 
				TC if PWM0 matches */				
    PWMMR0 = cycle;		/* set PWM cycle */
    PWMMR1 = cycle * 5/6;
    PWMMR2 = cycle * 2/3;
    PWMMR3 = cycle * 1/2;
    PWMMR4 = cycle * 1/3;
    PWMMR5 = cycle * 1/6;	

    /* all PWM latch enabled */
    PWMLER = LER0_EN | LER1_EN | LER2_EN | LER3_EN | LER4_EN | LER5_EN | LER6_EN;

    if ( install_irq( PWM0_INT, (void *)PWMHandler ) == FALSE )
    {
	return (FALSE);
    }
    return (TRUE);
}

/******************************************************************************
** Function name:		PWM_Set
**
** Descriptions:		PWM cycle setup
**
** parameters:			PWM cycle and offset
** Returned value:		None
** 
******************************************************************************/
void PWM_Set( DWORD cycle, DWORD offset )
{			
    PWMMR0 = cycle;		/* set PWM cycle */
    PWMMR1 = cycle * 5/6 + offset;
    PWMMR2 = cycle * 2/3 + offset;
    PWMMR3 = cycle * 1/2 + offset;
    PWMMR4 = cycle * 1/3 + offset;
    PWMMR5 = cycle * 1/6 + offset;

    /* The LER will be cleared when the Match 0 takes place, in order to
    load and execute the new value of match registers, all the PWMLERs need to
    reloaded. all PWM latch enabled */
    PWMLER = LER0_EN | LER1_EN | LER2_EN | LER3_EN | LER4_EN | LER5_EN | LER6_EN;    
    return;
}

/******************************************************************************
** Function name:		PWM_Start
**
** Descriptions:		Enable PWM by setting the PCR, PTCR registers
**
** parameters:			None
** Returned value:		None
** 
******************************************************************************/
void PWM_Start( void )
{
    /* All single edge, all enable */
    PWMPCR = PWMENA1 | PWMENA2 | PWMENA3 | PWMENA4 | PWMENA5 | PWMENA6;
    PWMTCR = TCR_CNT_EN | TCR_PWM_EN;	/* counter enable, PWM enable */
    return;
}

/******************************************************************************
** Function name:		PWM_Stop
**
** Descriptions:		Stop all PWM channels
**
** parameters:			None
** Returned value:		None
** 
******************************************************************************/
void PWM_Stop( void )
{
    PWMPCR = 0;
    PWMTCR = 0x00;		/* Stop all PWMs */
    return;
}

Hi Ajay

I am very sorry for creation of one more thread
I have not seen my thread in the “Project Help forum”, that’s why I have posted one more thread to the project help

After your reply I got my thread in the "ARM Development forum” now I will continue same thread

Thank you
Regards

chandu

you are welcome nattu enjoy!

Hay

What are the default settings for CLOCK in the LPC2106? I am using 14.7C64MHZ crystal
With out PLL & VPB Divider can I write programs, can I use 14.7MHZ crystal directly?
If i have not did any setting s in the LPC2106, then what is default clock

Thank you

Regards
chandu

the above picture shows how it is...
i would really like to know why you are against using PLL .
Pll and MAM increase the fuctionality of arm tremendously.


still if not using arm .. just use the external crystal.. and the clock will be same as in any controller . in your case 14.745Mhz.

if not using pll i wud suggest u to go for a crystall anywhere from 10-30Mhz.. but choose a round figure equation say 20Mhz. rather than 14.745
that will make your calculations easier.

hay
my circuit is generating 1KHz PWM pulses using LPC2106 micro controller My software is working well
I required some hardware help
I am planning to use L298 H Bridge Driver for my application, it have current sensing pins.
Please suggest switching optoisolater to isolate the LPC2106 with driver circuit & what hardware precautions I have to take to minimize the noise

Reagrds
chandu

try MCT2E or 4N32 opto coupler (single isolation), or MCT6E (2 isolators).