Bluetooth and UART raspberry pi zero w

Question

My objective is to get both data from VN200 GNSS/INS sensor (using GPIO14/15) and heart rate monitor strap Polar H10 (using Bluetooth) at the same time for synchronization.

Bluetooth on pi zero w by default use UART.

$ ls -l /dev/serial1
... /dev/serial1 -> ttyAMA0

$ ls -l /dev/serial0
No such file ...

After I switched Bluetooth mini-UART by adding these code to /boot/config.txt

dtoverlay=miniuart-bt
enable_uart=1
force_turbo=1

Now I got.

ls -l /dev/serial0
... /dev/serial0 -> ttyAMA0

ls -l /dev/serial1
... /dev/serial1 -> ttyS0

I want to use GPIO14/15 for primary UART to read data over VN200 sensor and bluetooth over mini-UART for reading data from heart rate strap. However, I noticed that both the ttyS0 and ttyAMA0 use same GPIO14/15 from this post, which either of them can be use.

My question is

• For certainty, is it possible to read 2 data at the same time? I doubt not.
• Do I have to use Bluetooth USB dongle for read HR data.

Answer 1

Your question is unclear as you have not elaborated what the "heart rate strap" requires.

It is only possible to use 1 serial port but you can use Bluetooth with mini UART. If you require 2 accessible UART you will need an additional adapter.

The Answer in the duplicate explains UART and how to swap although (unless your application requires high speed and/or parity) I have never found a need to swap UART.

Answer 2

For the Bluetooth communication with the Polar H10 heart rate monitor, using the mini-UART (ttyS0), you can use a Bluetooth library like BlueZ or other Python libraries that provide Bluetooth functionality. Make sure to pair and connect to the Polar H10 device using the Bluetooth address or device name.Bluetooth USB dongle should not be necessary in your current setup.

In case you want to make a GNSS HAT for a full fledged Raspberry pi, you can follow this design of GNSS HAT.