XavierTing
Posts: 2
Joined: Wed Jan 09, 2019 5:10 pm

HELP NEEDED! Couldn’t transmit through Uart

Wed Jan 09, 2019 5:25 pm

Good day,

I am a student working on my final year project which involve using raspberry pi 3. I am a beginner that never used raspberry pi before. I am currently trying to get the serial port working with my bluetooth module HC-05 to transmit some data to another bluetooth terminal which run on my android phone

I read online that the default serial port is used for console and I’ve followed the steps to disable serial port to console (via raspi-config/interfacing option/serial).

However I am still unable to receive any data when doing a simple ser.write with python. Really need to get this working to move on to the next step of my project. Any advise or help will be deeply appreciated. I have googled and tried to no avail.

Thanks in advance

Idahowalker
Posts: 445
Joined: Wed Jan 03, 2018 5:43 pm

Re: HELP NEEDED! Couldn’t transmit through Uart

Wed Jan 09, 2019 7:36 pm

Have you tried a loop back test? With a loopback test you can see if the RPi is set up properly. Entering the words 'raspberry pi serial loopback' into your favorite search engine will give you a plethora of options for a loop back test. Once you have completed a loopback test you can move outside of the RPi for the issue.
Without knowing why you are deleting my postings, I will not know how...

Andyroo
Posts: 3834
Joined: Sat Jun 16, 2018 12:49 am
Location: Lincs U.K.

Re: HELP NEEDED! Couldn’t transmit through Uart

Wed Jan 09, 2019 7:41 pm

Bit baffled as to the need for the HC-05 as the Pi 3s have built in bluetooth

Can you please provide:

1) The model of the Pi you are using
2) The version of the operating system
3) The contents of your /boot/cmdline.txt file

If you want to continue to use the HC-05 (they are prone to drop connection unlike the HC-06) then a simple diagram of the connection between the Pi and board would help.

I would suggest you also load minicom for testing as the HC units take AT commands and testing is simpler to start with rather than debugging Python as well.

Code: Select all

sudo apt-get install minicom
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XavierTing
Posts: 2
Joined: Wed Jan 09, 2019 5:10 pm

Re: HELP NEEDED! Couldn’t transmit through Uart

Mon Jan 14, 2019 5:23 pm

Previously worked with arduino and uses HC-05, thought of doing the same with raspberry as i do not know how to do serial transmit using the in-built bluetooth and python.

1) raspberry pi 3 model B
2) Rasbian (Linux)?
3)dwc_otg.lpm_enable=0 console=tty1 root=/dev/mmcblk0p7 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait splash plymouth.ignore-serial-consoles

connection is exactly the one shown here: http://icircuit.net/raspberry-pi-based-kiosk/380

Already have minicom installed.

Sorry for the late replies as i was away. i am really new at raspberry so i might catch on alittle slower, your simple guidance is surely appreciated.

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