How to get relaxation oscillator working. ** solved ** But now How to wakeup from deepsleep

[danjperron]

Ok Now That I got the oscillator working and able to switch this clock to the RTC.

How do I made the wakeup from deepsleep using the RTC.

This is my current clean code to get the RC oscillator from PIO20&PIO21 which drives the RTC.
Now I'm trying to figure out how to set the RTC to wakeup in deepsleep. I know that the Relax oscillator and the RTC still work on deepsleep

The code

Code: Select all

from machine import Pin,mem32,RTC
from rp2 import PIO, asm_pio
import time


IO_BANK0_BASE = 0x40014000
CLOCKS_BASE = 0x40008000
PADS_BANK0_BASE = 0x4001C000
RTC_BASE = 0x4005c000
RTC_CLKDIV_M1 = 0
RTC_CTRL = 0xc
RTC_0 = 0x1c
CLK_GPOUT0_CTRL = 0
CLK_GOUT0_DIV = 4

CLK_RTC_CTRL = 0x6c
CLK_RTC_DIV = 0x70
atomicXOR = 0x1000
atomicRW  = 0
atomicOR = 0x2000
atomicNOR = 0x3000

counter = 0

#set pins for GPIN0
def invertPinOut(pin):
    pin_addr = 4 + (pin *8)
    mem32[IO_BANK0_BASE | pin_addr | atomicNOR]= (0x3<<8)
    #set funcsel
    mem32[IO_BANK0_BASE | pin_addr | atomicOR]=  (0x1<<8)


pin20 = Pin(20,Pin.ALT,alt=8)
pin21 = Pin(21,Pin.ALT,alt=8)
invertPinOut(21)


#PIO to figure out the clock of the RC network
@asm_pio()    
def PIO_COUNTER():
    # Initialize x to be -1
    mov(x,0)
    label('loop')
    mov(isr,x)
    wait(0,pin,0)
    wait(1,pin,0)
    jmp(x_dec,'loop')
    jmp('loop')
    
def getPulse():
    global counter
    global sm1
    sm1.exec('push()')
    _tcount = sm1.get()
    pulseCount = counter - _tcount
    counter=_tcount
    return pulseCount
    


rtc = machine.RTC()

# this is to test if the clock of the RTC is ok
def CheckDatetime(header):
    print("--- RTC.datetime ",header," ---")
    for i in range(5):
       getPulse() 
       time.sleep(1)
       t=getPulse()
       print("Relax Osc count =",t,end="   ")
       print(rtc.datetime())





#state machine to check relaxation osc frequency
sm1 = rp2.StateMachine(1)
sm1.init(PIO_COUNTER,freq=125_000_000,in_base=pin21)
sm1.active(1)



def startRelaxationOsc():
    mem32[CLOCKS_BASE|CLK_GPOUT0_CTRL|atomicNOR] = 1<<11  
    # divide by 1
    mem32[CLOCKS_BASE|CLK_GOUT0_DIV]= 1<<8
    #enable clocks
    mem32[CLOCKS_BASE|CLK_GPOUT0_CTRL|atomicOR] = 1<<11
    #set clksrcpin0
    mem32[CLOCKS_BASE|CLK_GPOUT0_CTRL|atomicNOR] = (0xF << 5)    
    mem32[CLOCKS_BASE|CLK_GPOUT0_CTRL|atomicOR] = (0x1 << 5)


def setRTCToRelaxOsc(clock):
    mem32[RTC_BASE   | RTC_CTRL | atomicNOR] = 1 
    mem32[CLOCKS_BASE | CLK_RTC_CTRL | atomicNOR] = 1 << 11  
    mem32[CLOCKS_BASE | CLK_RTC_CTRL | atomicNOR] = 0x7 << 5
    mem32[CLOCKS_BASE | CLK_RTC_CTRL | atomicOR] = 0x4 << 5
    mem32[CLOCKS_BASE | CLK_RTC_DIV]=  1<<8
    mem32[RTC_BASE    | RTC_CLKDIV_M1] = clock-1
    mem32[RTC_BASE | RTC_CTRL | atomicOR] = 1
    mem32[CLOCKS_BASE | CLK_RTC_CTRL | atomicOR] = 1 << 11

getPulse()
CheckDatetime("initial")
startRelaxationOsc()
#record current time and osc counter
getPulse()
start_c = counter
start_t = time.ticks_ms()
CheckDatetime("after Relaxation oscillator")
#record the counter and the time to get an average
getPulse()
end_c=counter
end_t= time.ticks_ms()
avgClock = int((start_c - end_c) * 1000 / (end_t - start_t))
print("Relax. osc average clock = ", avgClock)
setRTCToRelaxOsc(avgClock)
CheckDatetime("after RTC input clock changed")

The script output shows that the RTC is still working fine . (less precise)

Code: Select all

>>> %Run -c $EDITOR_CONTENT
--- RTC.datetime  initial  ---
Relax Osc count = 0   (2022, 7, 14, 3, 23, 8, 50, 0)
Relax Osc count = 0   (2022, 7, 14, 3, 23, 8, 51, 0)
Relax Osc count = 0   (2022, 7, 14, 3, 23, 8, 52, 0)
Relax Osc count = 0   (2022, 7, 14, 3, 23, 8, 53, 0)
Relax Osc count = 0   (2022, 7, 14, 3, 23, 8, 55, 0)
--- RTC.datetime  after Relaxation oscillator  ---
Relax Osc count = 1697   (2022, 7, 14, 3, 23, 8, 56, 0)
Relax Osc count = 1698   (2022, 7, 14, 3, 23, 8, 57, 0)
Relax Osc count = 1697   (2022, 7, 14, 3, 23, 8, 58, 0)
Relax Osc count = 1699   (2022, 7, 14, 3, 23, 9, 0, 0)
Relax Osc count = 1697   (2022, 7, 14, 3, 23, 9, 1, 0)
Relax. osc average clock =  1529
--- RTC.datetime  after RTC input clock changed  ---
Relax Osc count = 1698   (2022, 7, 14, 3, 23, 9, 3, 0)
Relax Osc count = 1698   (2022, 7, 14, 3, 23, 9, 4, 0)
Relax Osc count = 1699   (2022, 7, 14, 3, 23, 9, 5, 0)
Relax Osc count = 1698   (2022, 7, 14, 3, 23, 9, 6, 0)
Relax Osc count = 1699   (2022, 7, 14, 3, 23, 9, 8, 0)
>>>