Toit driver for the MAX6675, a cold junction compensated K-thermocouple to digital converter. The driver implements the reading of data from MAX6675 over ESP32's native SPI interface or using GPIO pin bit banging.

jag pkg install github.com/krzychb/toit-max6675

The following example is using bit banging of GPIO pins.

import gpio
import max6675

//          ESP32 GPIO #  // MAX6675 Function (Pin)
cs_gpio ::=  gpio.Pin 12  // Chip select      (CS)
so_gpio ::=  gpio.Pin 13  // Serial output    (SO)
sck_gpio ::= gpio.Pin 14  // Serial clock     (SCK)


main:
  device := max6675.DriverBitBang
    --cs=cs_gpio
    --so=so_gpio
    --sck=sck_gpio

  max6675 := max6675.Driver device

  while true:
    print "Temperature: $(%0.1f max6675.read.temperature)°C"
    sleep --ms=500

See max6675.toit for an example of reading the temperature from MX6675 using SPI interface of ESP32.

• Toit is a modern high-level language designed specifically for microcontrollers.
• MAX6675 is a cold junction compensated K-thermocouple to-digital converter able to read temperatures in the range from 0°C to +1024°C.
• ESP32 is a feature-rich MCU with integrated Wi-Fi and Bluetooth connectivity for a wide range of applications.

• MAX6675 Cold-Junction-Compensated K-Thermocouple-to-Digital Converter (datasheet)

• Florian Loitsch was extremely helpful providing me with several tips on how to implement the driver.