Olimex ESP32-PoE love it but PINs problems?

[bluepr0]

Hello guys and happy new year!

My goal is to create a daughter board with built-in sensors (BH1750, SHT40, SCD41, and headers for DFRobot mmWave and Motion) that will connect to the header pins of the Olimex ESP32-PoE, that way I can get power and data through ethernet and make it as reliable as possible.

I have a Rev E board of the ESP32-PoE but I'm assuming the newer Rev K will be the same PIN usage and availability-wise.

That being said, I have been having some troubles with the PINS, it seems that some PINS will work okay and others won't depending on how I'm connecting and powering the board.

I want the board to work with PoE (data and power) but alternatively power it through a USB port or 5V input PIN through Wifi and be able to do OTA without problems in both cases.

After playing around I found some PIN configuration that works okay for all this, but I felt that the PIN out documentation it's not that accurate? (or maybe it's just me being a noob at this)

Currently, I'm using ESPHome with 2 UART buses, 1 I2C bus and 2 GPIO PINs, one for the motion sensor and another one for the mmWave one

Code Select Expand

i2c:
  - id: bus_a
    sda: GPIO16
    scl: GPIO15
    scan: true

uart:
  - id: uart_two  
    rx_pin: GPIO3 #19
    tx_pin: GPIO4 #18
    baud_rate: 9600
  - id: uart_mmwave
    tx_pin: GPIO14
    rx_pin: GPIO13

binary_sensor:
  - platform: gpio
    pin:
      number: GPIO33
      mode: INPUT_PULLDOW
  - platform: gpio
    id: mmwave
    device_class: occupancy
    pin:
      number: GPIO32
      mode: INPUT_PULLDOWN

And also use the regular PINs for the ethernet port (when enabled)

Code Select Expand

ethernet:
  type: LAN8720
  mdc_pin: GPIO23
  mdio_pin: GPIO18
  clk_mode: GPIO17_OUT
  phy_addr: 0
  power_pin: GPIO12

How do you guys see it?

Photos of the madness

[LubOlimex]

Thanks for the share! This is very cool and looks nice but if you want to power from PoE and USB maybe consider ESP32-PoE-ISO instead. ESP32-PoE might get damaged if you have PoE power and USB power applied SIMULTANOUSLY!

[bluepr0]

Thanks for the share! This is very cool and looks nice but if you want to power from PoE and USB maybe consider ESP32-PoE-ISO instead. ESP32-PoE might get damaged if you have PoE power and USB power applied SIMULTANOUSLY!

Thanks for the reply @LubOlimex. My idea is not to do it simultaneously, but to have the option to pick one or the other depending on the usage of the sensor or if I'm doing some test:
- PoE: this is probably going to be used when in the ceiling position at its final stage
- 5V Input: could also be on ceiling position if I don't have ethernet cable around or won't make too much sense for the type of sensor
- USB: if I'm doing some prototyping at my desk this is probably the one I will be using.

I hope in future revisions there's an USB-C added too

[bluepr0]

In case anyone is interested the multisensor shield board is available to download here https://oshwlab.com/bluepr0/olimex_shield_board_copy_copy