nPM1300 General Purpose Timer

[andychess]

Hi,

I can set up and run the GP timer on the nPM1300, but would like to know if the timer is running.  At first glance it looks like TIMERSTATUS (ca, p113 of the PS) should provide this information, but after a lot of experimentation, I can't get the value of the register to change. 

Could you please explain under what circumstances, the register changes and, if possible, give me a code snippet to illustrate it.

Many thanks, as always.

Andy   

[Benjamin]

Hi Andrew,

The TIMERSTATUS boot monitor bit indicates that the boot monitor has been requested. It does not indicate that the general-purpose timer is running. Unfortunately, there is no status bit available that reflects the timer’s running state.

Regards,
Benjamin

[andychess]

Hi Benjamin,

We figured that might be the case but couldn't workout exactly what influenced the register.  What exactly is the purpose of the register and when would we need it?

Best regards,
Andy  

[Benjamin]

Hi,
It is to read if the boot monitor is enabled or disabled. In the case of a firmware update you may want to check if the boot monitor is disabled. From the docs:

After a power-on reset, the default timer is boot monitor and this is disabled. When enabled, it allows an automatic power cycle if the host does not set bit TASK.TIMER.DIS within t_BOOT.

Host software can enable the boot monitor with bit BOOT.TIMER.EN. It can disable the boot monitor to prevent interference with firmware updates. When enabled, the boot monitor remains enabled even if the chip is reset, except for a power-on reset. Removing both VBAT and VBUS, or clearing the BOOT.TIMER.EN bit, deactivates the timer during the next power-up.

Regards,
Benjamin

[andychess]

Hi Benjamin,

Thanks for clarifying that.

Rgds,

Andy