MicroPython Forum (Archive)

I have some working MicroPython code that uses struct to send data from the micro:bit to another microcontroller board using I2C. I have converted the Python code to send buffered data 'one byte at a time' using the Javascript/Typescript window in https://makecode.microbit.org/ . For example: i2c.wr...

Nice!

You just need to work on the Grove ultrasonic module now

I know - I have one! They have produced a MakeCode package for the "Grove Inventor's Kit for micro:bit". The package includes support for the non-trivial devices in that Kit (Ultrasonic, 4x7-seg display and Gesture sensor). Very good stuff. Would be good to couple the Grove LED bar with the Grove ul...

Very nice! Thanks for that.

Mike
You are correct. Since you haven't had a reply here, maybe you should raise an issue on GitHub so the author can correct it?

I don't know. Have you tried putting a sleep(x) command in before the last uart.init(), where x is a delay in mSecs (e.g. 10)?

If you initialise the uart without parameters, I think that the USB-UART TX/RX pins are used - which connect to the USB serial convertor on the micro:bit. If you initialise the uart and specify which pins to use, like this uart.init(baudrate=9600, bits=8, parity=None, stop=1, tx=pin0, rx=pin1) then ...

Possible causes of no data at all:

1. Tx -> Rx
Rx -> Tx
not connected correctly

2. Baud rates/stop bits don't match at both ends.

I tried a range of resistances to attentuate the echo signal but it had no effect on the distance measurement.

It's a shame about the 5v requirement for this sensor. Your library gives consistent results so it's quite useable for collision avoidance.

I've got two power supplies with a common ground. The 5v supply just connects to the 5v and GND pins on the sensor. The micro:bit is powered from the 3.3V supply and the trig and echo pins on the sensor are connected to the micro:bit i/o pins.