A new version of the firmware is comming soon ... https://community.m5stack.com/topic/3321/unit-v2-connection

hi, don't know why but if you set that line n°31 in comment, it seems to work "# tvoc0.set_iaq_baseline(35187, 35502) while True: you may try to use the sample loop that you find in UIflow_Unit TVOC. As you can see on the picture below, TOVC/eCO2 can be use in a classroom context and it works fine I initialized it outside the window and came inside after [image: 1623533102839-mesures5-resized.png]

you input 5V level to the Device GPIO? .. the esp32 input voltage should lower than 3.6v. else it would be broken. I think your device was dead.

Thanks for your assistance

Hi, I found a solution. I have to limit the I2C frequency to 100,000kbps otherwise it won't work properly. This is strange because a frequency of 400,000 kbps works for all other devices and the MFRC522 should work fine at that frequency. If anyone has any idea on this limitation, I am very interested. Thank you

[image: 1623138336519-ff611ecf-3820-4f6b-b9b6-b31583e9c0d4-1623138255.jpg]

@m5stack said in The range of values from an ANGLE between directly connected to PORT B and connected to PORT A via PbHUB is different: ESP32 and mega328 has different ADC resolution Thank you very much for your reply. Yes, the ADC module on mega328 has a 10-bit resolution, whereas ESP32 has a 12-bit resolution. If this issue is just a resolution issue, the result should be 0 - 1023 instead of 15 - 745 or 0 - 715. If nobody can reproduce this issue, the PbHUB may be broken...

Thank you @flypeek, Apologies for the delayed response as I was on leave. Thank you so much and looking forward to going through it shortly. :) Cheers, Syd

Hello, the RCWL-9600 is very accurate. You may read the data using a simple function like this: #define M5_I2C_ADDR_ULTRA 0x57 float ReadI2CDistance() { uint32_t data; Wire.beginTransmission(M5_I2C_ADDR_ULTRA); Wire.write(0x01); Wire.endTransmission(); delay(120); Wire.requestFrom(M5_I2C_ADDR_ULTRA,3); data = Wire.read();data <<= 8; data |= Wire.read();data <<= 8; data |= Wire.read(); return float(data) / 10000; // distance in cm }

You can connect with Thonny and pull the .py files, modify and push back to the device.

@ckuehnel Did you ever figure this out? I just got my 18650 hat. I took it apart and also don't see any control circuitry. I'm now guessing that the USB connector on the hat simply feeds into the 5V input of the M5StickC, and the AXP192 inside the M5StickC controls the charge of the 18650 cell. There is some info in the AXP192 data sheet about a back-up battery, but it's been a while since I read it, and I'm not sure it's relevant. One interesting thing ... I'm working on a project where I turn the display off after a few seconds if the M5StickC is not plugged in. Either by shrewd design or by my dumb luck, that works when the M5StickC is on the hat. ("It works" means the display turns off after a few seconds.)

For my particular project I have a 8 digital IO that I am trying to connect and therefore would like to use the PbHub connected to the M5StickC to expand the IO (as they advertise). I also have the weight module which works fine if I connect this directly to the M5StickC grove port. So now I must choose between using a PbHub or a Weigh module. I had thought it possible to add the weigh module to one of the ports on the PbHub however after experimenting with different pin combinations for initializing the HX711 scale i.e. HX711 scale(33, 32); // This works when the weigh unit is connected to the grove port on the M5StickC // Below are the other combinations I tried for passing the necessary pins to the HX711 through the Mega328 without any success. //HX711 scale(porthub.hub_d_read_value_B(4), porthub.hub_d_read_value_A(4)); HX711 scale(porthub.hub_a_read_value(4), 32); //HX711 scale(porthub.hub_d_read_value_A(4), 32); //HX711 scale(porthub.hub_d_read_value_B(4), porthub.hub_d_read_value_A(4)); //HX711 scale(porthub.hub_d_read_value_A(4), porthub.hub_d_read_value_B(4)); Unfortunately, I think @felmue is right. The Mega328 isn't able to forward the clock required by the HX711 chip.

It is still not working. Can you please fix?

@devilstower, I am newbie. I think pbhub is only for digital/analog readings, ENV (i2c multiple data) sensor is out os scope for this I/O expander. The right one for ENV is pahub, as you confirmed. Try PIR, ANGLE or BUTTON on pbhub, worked for me. Bye.