LPC812-MAX: PWM example issue

[fjrg76]

Hi,

The example aims to dim a LED and and output, however the output (PIO0_6) doesn't dim. I thought it was a pullup issue, but it isn't. I was trying for hours in my own code, before to double check the example, to make the output get the PWM to work (10KHz, 50%) and I didn't succed. After trying the on-board PWM example the only thing I saw on my oscilloscope was an eternal 'hi' level at the PIO0_6 pin. Let me repeat that the output at PIO0_7 (red LED) works nicely. Something is missing on the example, any ideas?

[fjrg76 · Accepted solution]

SOLVED: PIO0_6 in the LPC812MAX serves as uart tx pin. And the uart is initialized as just mentioned in ALL examples, that's way there is no PWM on such pin. On other pins the PWM works as expected.

Still the uart can be disabled through global constant DEBUG in case someone needs a PWM output on PIO0_6.

[herusetiawan]

Hi Javier,

Could you share how to get the pwm source code for lpc812max?

thanks.

[zhouli]

I don't have this problem. I don't have LPC812, but LPC824 performance is similar to LPC812. No problem on PIO_6 output. You can try to connect the 0.5K resistor to VCC in PIO_6. Have a try。