TSP65910 RTC not running

Ben Henricksen

Other Parts Discussed in Thread: AM3715, TPS65910

RTC_CTRL_REG STOP bit is never being set.

What things should I be checking for?

I'm using linux derived software for the AM3715. I set the CTRL STOP bit and check the STATUS run bit and that's not set. When I re-read the CTRL STOP bit it is not set.

My 32kHz crystal is running OK. My main board is up and running fine - the RTC is one of the last jobs to do. I have done test write and read to the BACKUP Register and that checks out so I think my i2c comms are OK.

Any hints?

(I don't think there is an MSECURE bit on this device so I don't have to worry about that I hope.)

over 13 years ago

0 Flore Auzanneau over 13 years ago

TI__Intellectual 1820 points

Hello Ben,

Did you set DEVCTRL_REG.RTC_PWDON to 0 ? This will enable the RTC.

Best regards,

Flore

0 Ben Henricksen over 13 years ago

Intellectual 855 points

For clarification, from the TSP65910 manual:

Table 34. RTC_RESET_STATUS_REG

Address Offset 0x16

RTC register for reset status

5:0 RESET_STATUS RW 0x27

The diagram just shows bit 0 as active. Which is it and what does it do?

THanks.

0 Ben Henricksen over 13 years ago in reply to Ben Henricksen

Intellectual 855 points

Hi Flore,

That did it! DEVCTRL_REG PWRDN was set to 1.

This reg is not touched in the linux TPS65910 driver so I added a bit clear and it all sprang into life.

The manual doesn't mention it in the RTC section which is an omission.

THanks,

Ben

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TSP65910 RTC not running