5. Embedded Programming¶

Browse through the NuEval Handbook to review the evaluation criteria.¶

Group Assignment¶

Demonstrate and compare the toolchains and development workflows for available embedded architectures

In consultation with our instructor, we are each taking different views of the assignment, and reporting results here.

Albert ¶

Micropython, VSCode and RP2040 programming¶

To set up an environment to program a RP2040 with micropython using VSCode there are two major steps. One needs to prepare the RP2040 and load micropython. Then the VSCode environment needs to be prepared including necessary extensions.

Prepare RP2040¶

An online tutorial was instructive in getting started.

Put RP2040 into boot mode by holding B button and connecting computer via USB-C. This mounts the RP2040 as a drive

Download the current micropython. This is firmware which support an RP-2040 and micropython
Drag the resulting file onto the mounted drive. The RP2040 reboots and has micropython installed

Prepare VSCode¶

Ensure that Python 3.9 or newer is installed on system
Install Visual Studio Code
Install micropico extension in VSCode
In VSCode open project folder via ‘File/Open Folder…’
Via Control-Shift-P (Command-Shift-P on Mac) do ‘Micropico: Initialize MicroPico Project’

This configures and results in a message. A set of files is also created.

When the RP2040 is connected as noted above and these steps completed, there will be an indicator at the bottom of VSCode which says “Pico Connected.”

Now prepare to run code by creating a file with appropriate code

from machine import Pin
from time import sleep

led = Pin('LED', Pin.OUT)
print('Blinking LED Example')

while True:
  led.value(not led.value())
  sleep(0.5)

Pushing ‘Run’ at the bottom of the VSCode window results in a blinking LED on the RP2040.

LED blinking on RP2040

Documentation on the RP2040 is available on the micropython.org site.

This creates an environment to work with micropython in VSCode for the RP2040.

Anna ¶

Thonny¶

Thonny.org

There are 2 main options to install Thonny. If you have python already then you can just have python install Thonny for you.

pip install thonny

Alternatively you can install them in a bundle from thonny git. Or you can use the installer for Thonny alone. Make sure to select the correct installer. You if on a windows computer then “thonny-4.1.7.exe” is the installer you need. Then run the following code to ensure python is working with Thonny. Then do the pip install thonny in python.

First you can test python is working by running this code in Thonny.

Now Thonny is running and python is working. Let’s try to work with the micro controller.

ESP32-S3¶

This is a good tutorial for getting Thonny and the ESP32 running on your machine, Youtube Tutorial.

I was still having issues so I decided to follow the instruction on the on the Seeed Studios wiki ESP32S3. My opinion is to get the light blinking in arduino IDE before moving to Thonny.

After using Arduino you need to erase the chip. Go to windows powershell and use this code.

python -m esptool --chip ESP32-S3 erase_flash

If you need to erase the chip before loading micro python then this is the place to go. See link.

You can download the image for the chip here.

Chat GPT¶

Me - what is the mirco python code for blinking one led

GPT- 
Here's a simple MicroPython script to blink an LED connected to a GPIO pin (e.g., pin 2 on an ESP8266 or ESP32):

python
Copy
Edit
from machine import Pin
import time

led = Pin(2, Pin.OUT)  # Set GPIO 2 as an output pin

while True:
    led.value(1)  # Turn the LED on
    time.sleep(1)  # Wait for 1 second
    led.value(0)  # Turn the LED off
    time.sleep(1)  # Wait for 1 second

Explanation:
Pin(2, Pin.OUT): Initializes GPIO 2 as an output pin.
led.value(1): Turns the LED on.
led.value(0): Turns the LED off.
time.sleep(1): Pauses execution for 1 second.
Let me know if you need modifications (e.g., different pin, faster blinking, etc.). 🚀

Evert ¶

Programming ATtiny412 with Arduino IDE¶

What You Need:¶

ATtiny412 microcontroller
UPDI programmer (or an Arduino acting as a UPDI programmer)
Arduino IDE (latest version)
Serial UDPI cable
Serial UDPI 3 pin Addapter

Step 1: Set Up Support for ATtiny 1-Series in Arduino IDE¶

Open the Arduino IDE.
Go to File > Preferences.
In the “Additional Boards Manager URLs” field, add the following URL: Json file for arduino
Click OK to save.
Go to Tools > Board > Boards Manager.
Search for megaTinyCore and install it. This core supports ATtiny 0/1-series chips, including the ATtiny412.

Step 2: Setting Up the UPDI Programmer¶

The ATtiny412 uses the UPDI (Unified Program and Debug Interface) for programming. You have two options:

Option 1: Use an External UPDI Programmer¶

If you have a dedicated UPDI programmer (e.g., a USB UPDI programmer), connect it to the ATtiny412 as follows: - UPDI connection: Connect the UPDI pin of the programmer to Pin 2 (UPDI) on the ATtiny412. - Connect VCC and GND from the programmer to the VCC and GND pins of the ATtiny412.

add some stuff on how to program ATtiny412 with C++ in Arduino IDE

Magnus ¶

VSCode PlatformIO¶

I’m using PlatformIO in VSCode to program the Seeed Xiao RP2040 using Arduino/C++

I’m using the program I wrote in Assignment 9. Electronics Production.

This took me a surprisingly long time (four weeks) as PlatformIO does not have native support for the Seeed Xiao RP2040.

Research / Setup¶

I started off reading through forum posts and guides from people who’d done it successfully. I found this one from Tauno Erik on wordpress Tauno used PlatformIO’s settings menu and added https://github.com/maxgerhardt/platform-raspberrypi.git to PIO Home > Platforms > Advanced Installation then added the following into the platformio.ini file:

[env:seeed_xiao_rp2040];
platform = https://github.com/maxgerhardt/platform-raspberrypi.git#develop
board = seeed_xiao_rp2040
framework = arduino

I tried this but didn’t quite succeed. This forum post on the PlatformIO community forums held the answer. The thread had a response from maxgerhardt. The same maxgerhardt who’s behind the platform-raspberrypi fork linked earlier:

ForumAnswer

Okay. So I was missing longpaths in Windows. Following the link provided took me to a guide explaining this but when I went to open the Local Group Policy editor I couldn’t. Turns out it got removed in Windows 10 and 11 Home. Luckily I was able to find a thread on Microsoft’s Answers forum:

Forumpost

The post is densely worded but explains things well enough. Turns out you can install it from the Windows image packages. (The original Windows install media) by running the following commands in an elevated admin command prompt:

FOR %F IN ("%SystemRoot%\servicing\Packages\Microsoft-Windows-GroupPolicy-ClientTools-Package~*.mum") DO (DISM /Online /NoRestart /Add-Package:"%F")

FOR %F IN ("%SystemRoot%\servicing\Packages\Microsoft-Windows-GroupPolicy-ClientExtensions-Package~*.mum") "DO (DISM /Online /NoRestart /Add-Package:"%F")"

Roughly breaking this down. It goes through the two directories "Microsoft-Windows-GroupPolicy-ClientTools-Package" and "Microsoft-Windows-GroupPolicy-ClientExtensions-Package" and runs ""DO (DISM /Online /NoRestart /Add-Package:"%F")"" for each entry. DISM is “Deployment Image Servicing and Management”. In this case it’s doing DISM Add-Package with the /Online and /NoRestart arguments. These are all local files already in %SystemRoot% ( C:\Windows ) . It doesn’t fetch anything online but instead just adds the already present gpedit.msc packages to the Windows image.

This worked to enable the group policy editor. It now shows up when searching gpedit.msc in the start menu.

gpedit

Now to follow the rest of the steps. Opening gpedit and navigating to Local Computer Policy > Computer Configuration > Administrative Templates > System > Filesystem. The guide tells you to “Enable NTFS/Win32 long paths” In my case it’s called “Enable Win32 long paths”

GPEDIT Window

After making sure everything was working correctly I started a new PlatformIO project and started working.

Using PlatformIO¶

Installing PlatformIO is about as simple as any VSCode Extension. Just search PlatformIO in the VSCode Extensions tab and hit Install. It takes a while to sort everything out and you do need to restart VSCode to fully initialize it. Once that’s done you’ll have a new icon in the toolbar on the left.

Make sure you’re in a new VSCode window and not inside an already existing Git Repository. Click on the PlatformIO Icon and select “Create New Project” then you’ll be greeted with the “PIO Home” Tab. Click “New Project” and set it like so:

ProjectWizard

I temporarily set it to the Arduino Nano since it hasn’t pulled the configuration for the Xiao yet.

After creating the project navigate to platformio.ini and set it as follows:

[env:seeed_xiao_rp2040]
platform = https://github.com/maxgerhardt/platform-raspberrypi.git#develop
board = seeed_xiao_rp2040
framework = arduino
upload_protocol = uf2
monitor_speed = 115200

CTRL+S to save. The terminal window should light up with it fetching the relevant files from the Github page. This can take several minutes.

Once it’s done you can start using PlatformIO for the Xiao. Put your code in src > main.cpp and use CTRL+ALT+B or the dropdown in the top-right to build it. In the explorer toolbar on the left you can now navigate to .pio/build > firmware.uf2. That’s the file you’ll want to put onto the board.

Programming the board¶

Connect the Xiao to the computer while holding down the “B” button on the bottom-right of the board. It should pop up as a drive in file explorer. Once it’s there you simply drag and drop the firmware.uf2 file from .pio/build and it’ll eject itself automatically and start running your program.

I didn’t find a way to use PlatformIO’s “Deploy” functionality for the RP2040 but the Serial Monitor works, Down at the bottom of VSCode there’s a tab, Make sure to set it to the correct COM port and Baud rate. In my case it was COM4 USB Serial Device and the Xiao RP2040’s Baud rate of 115200.