rtc functionality in am335x

Athira Menon

Other Parts Discussed in Thread: AM3354

Hi,

We are building a system using AM3354. In the first version we have made, we have not been able to use the RTC functionality. We are aiming for a second version release by October. I s the RTC issue in AM3354 corrected? If not what are the workarounds for this?

The problem we are facing is this; The RTC stops incrementing when the power is switched off and resumes count from where it had stopped only after the power is on.

Any suggestions in this issue will be welcome..:)

Athira

over 11 years ago

0 kenneth Johansson over 11 years ago

Intellectual 310 points

There is an option to select clock source. are you running on a clock that is working all the time.

0 Athira Menon over 11 years ago in reply to kenneth Johansson

Prodigy 120 points

As of now we have an external 32KHz external crystal connected for clock..As our device is a real time one, the presence of the rtc is absolutely necessary..and this has not been implemented effectively because of the rtc problem in the earlier version of am3354..

0 kenneth Johansson over 11 years ago in reply to Athira Menon

Intellectual 310 points

I'm not sure what chip revision I'm using now but I have RTC working as a wakeup source so I can do

rtcwake -d /dev/rtc0 -m mem -s 5
and it wakes up after 5 seconds. but then I don't know if I turn power of as much as you do.

0 peaves over 11 years ago in reply to kenneth Johansson

TI__Guru 60825 points

The RTC issue described in the AM335x Silicon Errata Advisory 1.0.5 has been resolved in silicon revisions 2.0 and 2.1.

See Table 4 in the AM335x Silicon Errata.

Regards,
Paul

Processors

Processors forum

rtc functionality in am335x