HM-18 module for an Original 1.3b board?

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  • There are great instructions for adding a BLE 4.0 connection to an Espruino original board using the HM-10 module. Has anyone attempted to add a BLE 4.2/5.0 module such as the HM-18?
    It uses a CC2640 combatible chip.

  • Personally I haven't, but if it has the same pinout for GND/3.3v/RX/TX then I imagine the only difference would be in the commands you need to send to it...

  • HM-18 Module installs with the same pins as the HM-10 module. It’s advertised as BLE 5.0, and mine arrived with firmware v116, and there doesn’t seem to be an update for this module on the manufacturer’s website(­d=1).
    Like the HM-10, it is configured using AT commands, and has only two modes; iBeacon and a proprietary UART service. The AT commands can configure the module for lower-power and sleep modes. Gordon has posted iBeacon JS code at:­252971/

    I initially wired up a button and pull-up resistor to the System Key, pin 23. According to the data sheet, pulling to ground either disconnects a connected module or resets to a default configuration if already disconnected. Power cycling the module also disconnects, so I removed the button.

    I’ve configured a surface mount LE and 1206 resistor to shine through one of the board’s through-holes. Clear nail polish insulates the connections from the board, and the board still lays flat on a surface. The LED blinks when not connected, and stays on when connected.
    A simple script to control the on-board red LED can be controlled via the nRF Connect app to verify operation.

    function onInit() {
    Serial1.on('data', function(data) {
        if (data=="o") LED1.write(true); 
        if (data=="f") LED1.write(false); 

    Pretty nifty that a $5 add-on adds BLE communication to the versatile classic Espruino board!

  • For some reason I'm not able to embed images or attach them. Here are the links to the images in case anyone would like to see what I came up with:­master/1206Resistor_LED.JPG­master/HM18_LED.JPG­master/LED_BLE_Connect.JPG

  • That looks awesome - thanks for posting up!

    You say 'proprietary UART' - it's not the Nordic UART is it? If so you could then program Espruino with the Web IDE wirelessly - just like a Puck.js or other native Bluetooth LE device!

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HM-18 module for an Original 1.3b board?

Posted by Avatar for wminarik @wminarik