LPC1768 - PWM - load issue

[Dhaya]

Hi,

    We are working on LPC1768 and utilizing TIMER0,1,2,3, UART, I2C and External Interrupt. Along with this, tries to implement PWM with the frequency of 2.5MHz. But while configure the PWM with this frequency whole device get hold and cant execute any functionalities. In case of configuring, 500KHz or less than this everything works fine.

   Here PWM has configured to CCLK also instead of CCLK /4. 

    In case of create separate project only for PWM with frequency 2.5MHz, it works well. Kindly guide us get rid from this and  what may be issue in it. Is load of the controller may affect this?

[xiangjun_rong · Accepted solution]

Hi,

I suppose that you use interrupt mechanism, when you set up PWM with 2.5MHz frequency and enable PWM interrupt, the PWM ISR will be executed at 2.5MHz, it is a huge task for the core, the core will be overloaded, pls disable the PWM interrupt and have a try.

In order to have a test, pls toggle a GPIO in the forever loop in the main(), which can reflect the core workload status.

Hope it can help you

BR

XiangJun Rong