C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Thu, 08 Aug 2024 15:01:56 GMT

[mention:497ac2d0cd8d48c8a8de63258a1cb4cb:f7d226abd59f475c9d224a79e3f0ec07]

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Wed, 07 Aug 2024 21:16:42 GMT

since this release, I made the following changes to sturdy the code:

validate data string as well as status string

To cover scenarios where I receive an incorrect, but well-formed reply (it happens mostly after a previous reply failed), I now also validate that each reply string has the correct signature. It's done by checking if the characters 3 - 5 of the reply (these are constant for every type of reply) are the expected ones.

If not, the library returns an empty data result, and a count of 0 for multi line replies. The return value will be false.

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Sat, 03 Aug 2024 19:02:31 GMT

Since the release, I've made these changes to the nmake file:

more examples

There will be a

simple communication example to talk to the ST Teseo GPS, and
an example that uses this nmea parser in combination with talking to the Teseo GPS.

build firmware binaries for both UART and I2C

In version 1, you controlled with a compile definition, if firmware is for I2C or UART control.
At build time, it then created the binary for that protocol

In the next version, the standard build command will create the I2C and UART binary for each example.
You can still build a single selected binary, if you want that.
It's similar to what Pico does with its examples. Default build makes all of them, but you can ask to build one particular example.

It 'll make it easier to provide binaries when cutting a release.
It also serves as a proof that you can use these libraries for both protocols without code changes or conditional constructs.

This is already available on GitHub develop and main branch.

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Thu, 01 Aug 2024 18:20:57 GMT

Since the release, I've made a few changes to the structure:

all pico specific code (init, reset, read and write) is moved out of main.cpp.
These device dependent functions now reside in the port/pico subfolder.
goal: make it easier to create ports for other controller families

the library core files have their own github repository now,
and I changed this project's git setup and build infra to use that repo as a subfolder.
goal: make it easier for users to just get / use the pure library, without getting the Pico specific examples and code

If you do a clean checkout, you can use this command to get the project and the submodule in one go:

git clone github.com/.../pico_gps_teseo.git --recursive

If you already have a local repository, take care that it has latest changes (git pull),
and then retrieve submodule:

git submodule init
git submodule update

if you want to add the lib to your own project, execute this from the project's root folder:

git submodule add https://github.com/jancumps/gps_teseo_lib.git

GitHub repo: https://github.com/jancumps/pico_gps_teseo

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Wed, 24 Jul 2024 19:45:43 GMT

GSA and GGA message added. That completes the list of data that the device outputs by default.
For other messages (there are a lot), a developer can use the libraries reader, writer and line parser methods to query them.

currently available in the develop branch.

GLL valid: yes.
$GPGLL,5051.76917,N,00422.58021,E,194121.000,V,N*4A
GSV valid: yes. count: 5.
$GPGSV,3,1,11,13,86,080,,15,58,293,,14,55,091,,22,55,131,*70
$GPGSV,3,2,11,05,38,205,,30,35,070,,24,19,256,,23,15,324,*7C
$GPGSV,3,3,11,20,14,189,,18,10,286,,07,05,069,11,,,,*47
$GLGSV,2,1,08,74,65,048,,72,64,140,23,75,54,209,,65,52,318,24*61
$GLGSV,2,2,08,73,20,040,37,71,14,139,,82,12,004,30,81,08,319,28*6D
GSA valid: yes. count: 2.
$GNGSA,A,1,,,,,,,,,,,,,99.0,99.0,99.0*1E
$GNGSA,A,1,,,,,,,,,,,,,99.0,99.0,99.0*1E
GGA valid: yes.
$GPGGA,194124.000,5051.76917,N,00422.58021,E,0,00,99.0,065.76,M,0.0,M,,*61
RMC valid: yes.
$GPRMC,194125.000,V,5051.76917,N,00422.58021,E,,,240724,,,N*7E

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Sun, 21 Jul 2024 16:47:55 GMT

Why I selected std::vector as container in this lib: https://embeddedartistry.com/blog/2017/08/23/choosing-the-right-stl-container-general-rules-of-thumb/

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Sun, 21 Jul 2024 14:45:29 GMT

With a few tweaks, it builds in the Arduino IDE too:

I had to downgrade some C++ constructs that aren't available in the GCC versions that ship with the IDE:

This optional one I commented out for Arduino and other older toolchains. It's a guard, not executable code.

[embed:dc8ab71f-3b98-42d9-b0f6-e21e02a0f8e2:5342357f-544f-4114-8410-20349a42c937:type=c_cpp&text=%23ifdef%20__GNUC__%20%2F%2F%20this%20requires%20a%20recent%20version%20of%20GCC.%0D%0A%23if%20__GNUC_PREREQ%2810%2C0%29%0D%0A%20%20requires%20std%3A%3Ais_void%3CR%3E%3A%3Avalue%20%7C%7C%20std%3A%3Ais_arithmetic_v%3CR%3E%0D%0A%23endif%0D%0A%23endif%0D%0A]

The std::string class in Arduino's toolchain doesn't support starts_with() yet. I replaced it (for older compilers) with a find(). My code is not exactly the same, but will fit in this scenario.

[embed:dc8ab71f-3b98-42d9-b0f6-e21e02a0f8e2:f96e4f56-6798-4694-a67d-a773640e2093:type=c_cpp&text=%23ifdef%20__GNUC__%20%2F%2F%20this%20requires%20a%20recent%20version%20of%20GCC.%0D%0A%23if%20__GNUC_PREREQ%2810%2C0%29%0D%0A%20%20%20%20%20%20%20%20%20%20%20%20valid%20%3D%20s.substr%28string_index%2C%20s.length%28%29%20-%20string_index%29.starts_with%28command.second%29%3B%0D%0A%23else%0D%0A%20%20%20%20%20%20%20%20%20%20%20%20valid%20%3D%20%28s.substr%28string_index%2C%20s.length%28%29%20-%20string_index%29.find%28command.second%29%29%20%21%3D%20std%3A%3Astring%3A%3Anpos%3B%0D%0A%23endif%0D%0A%23endif]

I'm not ready to test yet - I still have to write the reader and writer. But this is a good start.

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

Jan Cumps — Sun, 21 Jul 2024 12:40:00 GMT

the binary firmware is for I2C. If you want to run over UART:

change the CMakeLists.txt. Comment out the I2C define, and uncomment the UART define:

# select the communication protocol to talk to the Teseo GPS
add_compile_definitions(GPS_OVER_UART)
#add_compile_definitions(GPS_OVER_I2C)

and rebuild using your usual Pico build workflow.

RE: C++ library for ST Teseo GPS - pt. 5: ready for a first (0.1) firmware release

shabaz — Sun, 21 Jul 2024 11:53:50 GMT

Fantastic work on taming it. This now opens up all sorts of time and navigational projects!! This is a great reference to work with, for anyone using the ST Teseo products.