The SparkFun OpenScale - IoT offers an easy-to-use wireless solution to measure weight and temperature. This updated version of the original SparkFun OpenScale works with multiple load cell types and lets users access the device over multiple interfaces of their choosing. The OpenScale IoT communicates wirelessly over Bluetooth®/BLE as well as over a wired serial connection over USB-C or serial port to configure calibration value, sample rate, time stamp and units of precision through the OpenScale's serial menu. The board can to connect to a 2.4GHz WiFi network to view data from the board but it cannot be configured over a WiFi connection as it is read only.
Building a scale with the OpenScale - IoT is easy. Simply attach a four-wire or five-wire load cell of any capacity, connect to it via Bluetooth/BLE (or over USB-C/serial if you prefer) and open a terminal window at 115,200bps and you'll immediately be able to calibrate and configure the scale and get weight readings. Connecting the OpenScale - IoT to a Bluetooth host device requires a terminal application installed on it so if you're connecting it to a phone, make sure to install a terminal application of your choice. Unfortunately, the OpenScale - IoT is not supported on Apple devices.
Users can also connect the OpenScale - IoT to a WiFi network after entering the network's credentials (network name and password) into the configuration menu. The OpenScale - IoT also supports over-the-air (OTA) firmware updates while connected to a WiFi network. Note: The firmware update command must be sent through a terminal connection over either Bluetooth or serial.
The OpenScale - IoT is built around the ESP32 Pico Mini module that handles firmware and communication (both wireless and wired) and transferring scale and temperature data to a serial terminal . It also handles communication with the HX711, a 24-bit ADC for weigh scales; and the TMP102, for recording the ambient temperature of your system.
- /docs - Images used in the hookup guide
- /firmware - OpenScale - IoT firmware
- /hardware - KiCad Files
- Hookup Guide - Basic hookup guide for the SparkFun OpenScale - IoT
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