STM32L471 TIM6 & TIM7 problem

[jh2]

Posted on November 21, 2016 at 15:21

Hi,

I seem to have issues with TIM6 and TIM7 (the enable bit seems to directly be turned to 0 when I write it to 1) in OPM (One Pulse Mode) when I have a 1.8V power supply. The timers (both) seem to operate properly when I use a 2.2V power supply. 

Is this a known problem or am I doing something wrong? (I did not see any mention of this in the errata file).

Best regards,

JH.

#tim6 #low-power #stm32l471 #tim7

[waclawek.jan]

Posted on November 22, 2016 at 07:43

Is the problem restricted to OPM?

Are there outputs to pins/external hardware from these timers?

JW

[jh2]

Posted on November 22, 2016 at 14:45

Hi, thank you for your answer.

I didn't test any other other configuration than OPM. Actually I initiate the timer and use it as a timeout in a polling loop. Works perfectly (2ms when VCC=2.2V on the same board or 3.3V on another board - completely different design, but same CPU), by waiting for the EN flag to get reset by hardware. With 1.8V, the bit is directly read as 0 and my wait aborts.

JH.

[waclawek.jan]

Posted on November 22, 2016 at 14:59

And other timers do work as expected? Do TIM6/TIM7 run at all?

Post readback content of relevant RCC and timer registers, just after the enable bit is read as 0.

JW