Hello,
currently we want to use the sleep and deep sleep mode on TM4C1231E6PZ.
We tried to wake up from these modes with the RTC -> This works very well.
But wake up from these modes with the #WAKE (Pin 50) pin doesn't work. -> No interrupt is generated.
In the datasheet the wake pin (pin 50) is a possible wake up source for the sleep modes.
Do you have an idea what the problem coud be?
Thanks
chris
Hi Chris,
I jump in here for my customer Christoph. Basically they want to use the sleep mode/deep sleep mode of the controller.
To wake up the controller from these modes we would like to use the #Wake pin (50) from the Hibernation module. According to the datasheet this should work -> but unfortunately it doesn't.
They compiled this summary:
In the same way as RTC triggers an interrupt, the /wake pin should if configured accordingly.
The only differences are the bit positions in the hibernation interrupt registers.
The TM4C1231EPZ manual (June12, 2014, page 487) describes the EXTW bit in the Hibernation Raw Interrupt Status (HIBRIS), offset 0x018 as follows:
We also can read, that this bit works also in the run and sleep modes!
Unfortunately I can’t see this!!
Bit 0 of the same Register is for the RTC match interrupt which wakes-up my system from (deep) sleep by the hibernation interrupt as expected:
Interrupts will be forwarded to the interrupt controller if the corresponding mask bits in the Hibernation Interrupt Mask (HIBIM), offset 0x014 are set. The manual describes the bit for /WAKE as follows:
This is in accordance with e.g. the mask bit for the RTC alert which works well:
All hibernation interrupts are routed via the NVIC to the same interrupt vector. The fact that the RTC pulls my system out of (deep) sleep and calls my hibernation interrupt service, proves that the interrupt system is configured correct.
What I find suspicious is, that I never found the EXTW bit set in the HIBRIS register. To me, this explains why no hibernation interrupt occurs and the controller doesn’t wake-up.
On the other hand, if I hibernate the system, the /WAKE works well and the hibernation interrupt service is called. So I assume that the /WAKE signal is routed correctly. Which is also checked with the scope.
It seems to me, that in run an sleep modes a ‘link’ between the signal on the /WAKE pin and the EXTW bit in the HIBRIS register is missing.
Is there a condition not fulfilled, to forward the /WAKE signal to the EXTW bit in HIBRIS?
That this should work is e.g. mentioned on page 474, chapter 7.3.12 Interrupts and status:
Or simply is the silicon faulty at his point? If so, a errata clarifying this would be enormous helpful!
Regards Bernd
