Pressure, temperature and humidity sensor based on MS5637 HDC1080

This is anothe small module to measure air pressure, temperature and humidity. Two sensors are on-board: MS5637 and HDC1080. Microcontroller is small cortex M0 in TSSOP-20 housing from STM: STM32F070CxP. The SN65HVD72DGKR provides RS485 interface functionality with half duplex mode. Voltage regulator, reverse polarity protection and some LED indicators are provided on-board. Complete module is 10x55mm, produced on single-sided PCB, easily producible in every home lab with proto-PCB capability.

RH, T and air pressure sensor with RS485

RH, T and air pressure sensor with RS485

Firmware for the sensor is on the GitHub in my MS5637_HDC1080 repository.

Sensor has default HDLC address 0x31 and unique ID 0x0d000011.

Initial version has  following HDLC commands

enum
{
    CMD_Temperature = 0x40, /// Temperature readout from hdc1080
    CMD_Humidity,           /// Humidity readout from hdc1080
    CMD_Bat,                /// battery readout from hdc1080
    CMD_Pressure,           /// Air pressure in hPa or mbar abs
    CMD_pTemperature,       /// Temperature readout from pressure sensor
    CMD_pCAL,               /// Calibration coefficients from pressure sensor
    CMD_pD1,                /// Raw pressure readout from pressure sensor
    CMD_pD2,                /// Raw temperature from pressure sensor
    CMD_ID,                 /// Identification
};

Drivers for both sensors are:

https://github.com/s54mtb/MS5637_HDC1080/blob/master/src/hdc1080.c
https://github.com/s54mtb/MS5637_HDC1080/blob/master/src/MS5637.c


Other project resources:

rhtp-pcb

Single sided PCB

 

rhtp-sch

Schematic diagram

“Toner transfer” artwork for single sided PCB: RHTP

Here is complete documentation for the PCB, schematic and BOM:

RHTP-projectPCB-doc

3 Comments

  1. Damo says:

    Bok,

    te zanimajo senzorji temperature in vlage Si7013 in Si7021? Imam vzorce, pa ti lahko kakega odstopim (ti prinese Karmen). So kar hitri v Si, v 4 dneh sem jih dobil.

    lp, damjan

  2. Damo says:

    Dobiš. Zanimivo bi bilo tudi narediti varianto s CC1101 namesto 485 komunikacije.

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