create 2 serial ports?

[david_1234]

Hello ,
Using PI4 buster
currentlly I'm using pin8 and pin 10 to read data from Arduino (which is Serial0)
I need to read another Arduino , so I need to connect it to another serial port
when I look at the pinout I see I can use pins 27&28 as Tx2\Rx2
do I need to change something in the condig file? boot.txt in order to work with this pins?
or I can just connect and in the code write /dev/Serial2 ?

Thanks,

[ElEscalador]

Based on your headline I came to say that I know you can use pigpio to bitbang with any gpio, but if I have to write as well as receive (at the PI) I usually just use an FTDI because it's a little bit of a dance to create waves. But I see you ask about the PI4 and I forgot it has a "2nd uart" so now I'm commenting largely to follow also because sooner or later I'll take the 4GB model I've had since release week out of the box.

[david_1234]

Didn't understand what you want to say ,

After seraching online
I saw that I jsut need to add in /boot/config.txt this line:

Code: Select all

enable_uart=1
dtoverlay=uart2

then to use this setting in python code

Code: Select all

ser = serial.Serial(
               port='/dev/serial1',
               baudrate = 9600,
               parity=serial.PARITY_NONE,
               stopbits=serial.STOPBITS_ONE,
               bytesize=serial.EIGHTBITS,
               timeout=1

tehn I use pin28 (RX) to get the data from my sensor - and it's working!

but when I use the same setting in another PI4 - it doesn't work

I don't get any reading at all - what can it be?
using the same sensor \cables \wiring ....

Thanks ,