Calliope Mini BC95 NB-IoT Module

This is a package for controlling an NB-IoT module to send messages from the Calliope mini. It can be used by the PXT Calliope mini editor. Should also work with PXT for Micro:bit.

More information on the module can be found on the Quectel website. It is used in conjunction with an evaluation kit.

The code may be used as a starting point for similar AT based systems.

Testing

Modify tests.ts to send packages to your own server. Execute a little server: nc -vv -ul -p 5883 (Linux also echos the messages). Compile the test pxt test and copy built/binary.hex to the Calliope mini.

In the USB console window, you will see this:

START TEST
TEST: modem working: OK
TEST: enable all functionality: OK
TEST: check IMSI: OK
TEST: connect to network: OK
TEST: check signal quality: OK
TEST: check network stats: OK
TEST: check PDP context: OK
TEST: check address: OK
TEST: check band: OK
TEST: ping external server: OK
TEST: expect ping reply: OK
TEST: sending number: OK
TEST: sending string: OK
TEST FINISHED OK

You can follow the AT flow on the USB serial console by enabling debug in tests.ts

The server should show something like this:

connect to [46.23.86.61] from tmo-121-137.customers.d1-online.com [80.187.121.137] 25519
 {"id":"bc9ab239","p":{"test":123}}{"id":"bc9ab239","p":{"test":"value 123"}}

Example

Blocks: Javascript

input.onButtonPressed(Button.A, () => {
    bc95.sendString(
        "Hallo",
        "Calliope mini"
    )
    if (bc95.sendOk()) {
        basic.showIcon(IconNames.Yes)
    } else {
        basic.showIcon(IconNames.No)
    }
    basic.pause(1000)
    basic.clearScreen()
})
input.onButtonPressed(Button.B, () => {
    bc95.sendNumber(
        "t",
        input.temperature()
    )
    if (bc95.sendOk()) {
        basic.showIcon(IconNames.Yes)
    } else {
        basic.showIcon(IconNames.No)
    }
    basic.pause(1000)
    basic.clearScreen()
})
bc95.init(
    SerialPin.C17,
    SerialPin.C16,
    BaudRate.BaudRate9600
)
bc95.attach()
bc95.setServer("46.23.86.61", 5883)
$ listening on [any] 5883 ...
  connect to [46.23.86.61] from tmo-121-137.customers.d1-online.com [80.187.121.137] 24189
  {"id":"bc9ab239","p":{"t":29}}{"id":"bc9ab239","p":{"Hallo":"Calliope mini"}} 

To Do

• extract AT response parsing into its own module to make it usable for other devices

• handle incoming messages

Meta

• PXT/calliope

• PXT/microbit

Author: Matthias L. Jugel (@thinkberg)