How to read data from the on-chip temperature Sensor in circuitpython

[HonestQiao]

How to read data from the on-chip temperature Sensor in circuitpython？

[SeasonMay]

I have the same question,official examples provide codes concerning temperature which use the library of“sensor”,but i cannot find this lib in my circuitpython .bin file(version 8.2.9)

[HonestQiao]

I checked the datasheet of efr32mg24 and learned that it may be necessary to read register data from memory mapping. However, circuitpython on efr32mg24 does not have a memoryio module!

[HonestQiao]

We have found a suitable way to read it.

Compile a circuitpython by yourself and enable uctypes.
Use the version I compiled:
adafruit-circuitpython-explorerkit_xg24_brd2703a-en_US-9.0.0-alpha-uctypes.zip

import uctypes
from uctypes import BF_POS, BF_LEN
from uctypes import UINT32, BFUINT32, BFUINT16, BFUINT8, struct
import time

# EMU base address
EMU_ADDR_BASE =0x50004000

# EMU Temperature Register offset
EMU_ADDR_TEMP_OFFSET = 0x088

# EMU Status Register offset
EMU_ADDR_STATUS_OFFSET = 0x084

# EMU Command Register offset
EMU_ADDR_CMD_OFFSET = 0x070

# EMU Temperature and Status data struct
EMU_LAYOUT = {
    "EMU_TEMP": (
        EMU_ADDR_TEMP_OFFSET,
        {
            "TEMP": 2 << BF_POS | 9 << BF_LEN | BFUINT32,
            "TEMPLSB": 0 << BF_POS | 2 << BF_LEN | BFUINT32,
            "TEMPAVG": 18 << BF_POS  | 9 << BF_LEN | BFUINT32,
            "TEMPAVGLSB": 16 << BF_POS | 2 << BF_LEN | BFUINT32,
        }),
    "EMU_STATUS": (
        EMU_ADDR_STATUS_OFFSET,
        {
            "TEMPACTIVE": 2 << BF_POS | 1 << BF_LEN | BFUINT8,
            "TEMPAVGACTIVE": 3 << BF_POS | 1 << BF_LEN | BFUINT8,
        }),
    }

# print size of EMU_LAYOUT
#print(uctypes.sizeof(EMU_LAYOUT))

# EMU_CMD map
emu_cmd = uctypes.bytearray_at(EMU_ADDR_BASE+EMU_ADDR_CMD_OFFSET, 1)

while True:
    # send EMU_CMD_TEMPAVGREQ command
    emu_cmd[0] = emu_cmd[0] | 0x10

    # emu map
    emu = struct(EMU_ADDR_BASE, EMU_LAYOUT)

    # print status of EMU Temperature sensor
    #print(emu.EMU_STATUS.TEMPACTIVE, emu.EMU_STATUS.TEMPAVGACTIVE)

    # print currect Temperature value
    T1 = emu.EMU_TEMP.TEMP
    T2 = emu.EMU_TEMP.TEMPLSB
    Tk = T1 + T2/4
    Tc = Tk - 273.15
    #print([T1, T2, Tk, Tc])
    
    # print avg value of Temperature
    T1 = emu.EMU_TEMP.TEMPAVG
    T2 = emu.EMU_TEMP.TEMPAVGLSB
    Tavgk = T1 + T2/4
    Tavgc = Tavgk - 273.15
    #print([T1, T2, Tavgk, Tavgc])

    print("Temp avg: %0.2f, Temp curr: %0.2f" % (Tavgc, Tc))

    time.sleep(0.5)