topic Re: LPC4350 Simultaneous LPC_TIMER0 reads from M4 and M0 in LPC Microcontrollers

LPC4350 Simultaneous LPC_TIMER0 reads from M4 and M0

gregdunn — Fri, 11 Jan 2019 16:08:24 GMT

Is there any problem with initializing LPC_TIMER0 on the M4 core and then calling Chip_TIMER_ReadCount(LPC_TIMER0) asynchronously on both the M4 and M0 cores to allow for synchronized timing functions between both cores?

Thanks,

Greg Dunn

Re: LPC4350 Simultaneous LPC_TIMER0 reads from M4 and M0

bernhardfink — Fri, 11 Jan 2019 16:23:01 GMT

There shouldn't be a problem. Both cores are bust masters and can read at any point in time from peripheral resources. The one which reads first will get first.

What is always dangerous:

while (x < 1000)

{

x = read_timer(timer0);

}

If you poll with full CPU speed on a register, even simultaneously with two different cores, then you might see weird system behavior.

Regards,

Bernhard.

Re: LPC4350 Simultaneous LPC_TIMER0 reads from M4 and M0

gregdunn — Fri, 11 Jan 2019 18:30:03 GMT

Thank you very much for the clarification!

Greg