GPS Receiver connected to UART on Raspbberry Pi Zero W

General discussion about anything related to Ultibo.
develone
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Joined: Wed Dec 28, 2016 7:40 pm
Location: El Paso Tx USA

GPS Receiver connected to UART on Raspbberry Pi Zero W

Postby develone » Fri Jul 21, 2017 10:54 pm

GPS Receiver connected to UART on Raspbberry Pi Zero W.
Testing using Minicom in Raspbian and Examples/13-SerialConnection/RPi.

The Minicom Raspbian did not work. Search of the WEB has posts that UART is
not working.
see dated Mar 14 2017
https://www.raspberrypi.org/forums/view ... &p=1132033

Will Ultibo support overlays in the future?

The Ultibo verison worked okay.

Raspberrypi Zero W using ADAFRUIT ULTIMATE GPS FEATHERW
The ADFRUIT model was suppose to be better since it used ¨WAAS¨

For more information see
https://github.com/develone/EKIS/blob/master/presentations/Raspberrypi_baremetal.ppt

This also features pik33 window manager.
This is some presentations I am working on for getting in the schools here in El Paso,

Cheers
Gavinmc42
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Joined: Sun Jun 05, 2016 12:38 pm
Location: Brisbane, Australia

Re: GPS Receiver connected to UART on Raspbberry Pi Zero W

Postby Gavinmc42 » Sat Jul 22, 2017 1:23 am

When the WiFi/BT was added FPF swapped the Uarts.
TX0/RX0 on the Header is now the miniuart Page 8 manual.
The BT chip uses Uart 1 page 175.

This shows mini uart is not supported yet
https://ultibo.org/wiki/Supported_Hardware

Page 102 show the peripheral alternatives for the header 14/15.
As the WiFI/BT is not yet supported by Ultibo, you could alt5 the GPIO pins 14/15 to use the PL011 uart.
Not sure if Ultibo defaults to this option?

Once Wifi/BT is working then the mini uart will need to be done else the uart on the header is unusable.
Considering how long it took RPF to sort out these issues it does not sound like it is that easy :(

Considering the documentation, I still regard Ultibo as a little miracle that so much works.
Some things like i2c seems to work even better than the Linux i2c stuff.
You could try stuff like this, 1st google
https://www.sparkfun.com/products/retired/9981

FTDI is supported if you want to use the USB interface.
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Ultibo
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Location: Australia

Re: GPS Receiver connected to UART on Raspbberry Pi Zero W

Postby Ultibo » Sat Jul 22, 2017 4:45 am

develone wrote:Will Ultibo support overlays in the future?

Maybe one day, the format of the device tree information is documented (in the Linux code at least) so it would be possible.

Part of the problem is that the information is very much tailored to Linux and the way it works, which sometimes is not the way the rest of us think things should work.

develone wrote:This is some presentations I am working on for getting in the schools here in El Paso,

I would encourage you to also look at the MagPi magazine (free to read online) and the Raspberry Pi Weekly which both have lots of great project ideas, many of which could be easily ported to Ultibo in order to create something to demonstrate what can be done.

A really simple idea for a bare metal demo would be to take the Mouse Drawing example and extend it to include selecting the color to draw with and erasing the drawing to start over, a fun project that is both practical and engaging for young learners.
Ultibo.org | Make something amazing
https://ultibo.org
develone
Posts: 200
Joined: Wed Dec 28, 2016 7:40 pm
Location: El Paso Tx USA

Re: GPS Receiver connected to UART on Raspbberry Pi Zero W

Postby develone » Sun Jul 23, 2017 3:40 pm

Thanks to Gavinmc42 & Ultibo for the information they provided.

Removed
console=serial0,115200 console=tty1
from the file /boot/cmdline.txt

Configured and saved the minicom parameters.

Serial Device : /dev/serial0
Bps/Par/Bits : 9600 8N1
Hardware Flow Control : No
Software Flow Control : No

Now Raspbian minicom works.
see the histograms of elevation, lat, and long I created using octave.

https://github.com/develone/EKIS/tree/master/octave/fig

Also this receiver appears to be a bit better than pmod receiver.

see on DGPS

https://github.com/develone/EKIS/blob/master/gps_info.txt


Cheers,

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