Other Parts Discussed in Thread: TMDSEVM437X, TMDXSK437X
Hi all,
I have a question that can not be backed up AM437x's RTC.
I tested RTC backup with the following two patterns.
(1) HW:TMDSEVM437X
SW:PROCESSOR-SDK-LINUX-RT-AM437X 03_03_00_04 & I use prebuild image.
I connected the battery(Coin Cell) to the EVM and turned off/on the AC adapter in that state.
While the AC adapter is not connected, VDDS_RTC keeps 1.8V.
With this configuration RTC is backed up as follows.
~#hwclock
Web Dec 14 23:26:29 2016 0.000000 seconds
------ Turn off/on the AC adapter ------
~#hwclock
Web Dec 14 23:27:05 2016 0.000000 seconds <-- "Time is progressing normally"
(2) HW:TMDXSK437X
SW:PROCESSOR-SDK-LINUX-RT-AM437X 03_03_00_04 & I use prebuild image.
As in (1), Coin-cell is connected.
While the AC adapter is not connected, VDDS_RTC keeps 1.8V.
With this configuration RTC does not back up as follows.
~#hwclock
Web Dec 14 23:26:29 2016 0.000000 seconds
------ Turn off/on the AC adapter ------
~#hwclock
Web Dec 14 23:26:12 2016 0.000000 seconds <-- "Time is back"
I think that the program for TMDXSK437X is overwriting the RTC register
How can I perform RTC backup on TMDXSK437X?
Best regards,
Sasaki