Simmel Scrypts

Prerequisites

We assume the following:

• You are running on an Raspberry Pi 4
• You have openocd compiled. Recursively clone it from https://github.com/ntfreak/openocd.git, Configure it with

./configure --enable-sysfsgpio --enable-bcm2835gpio

and install it. This is tested against commit a1c51caafbac67df36dbecb27dd4b195730354b9.

If you are not using a Raspberry Pi 4, check the rpi-simmel.cfg file and uncomment the lines corresponding to the model that you're using.

Getting Started

Clone and build the following items:

The Bootloader is at https://github.com/simmel-project/bootloader.git

git clone [email protected]:simmel-project/bootloader.git
cd bootloader
git submodule init
git submodule update
make BOARD=simmel

Building Circuit Python (the first time)

Circuitpython is at https://github.com/simmel-project/circuitpython.git

git clone https://github.com/adafruit/circuitpython.git
cd circuitpython
git submodule init
git submodule sync
git submodule update
cd ports/nrf
make BOARD=simmel

You will want build-simmel/firmware.uf2. If you're debugging, you'll also want build-simmel/firmware.elf.

Initial programming needs a build of openocd in order to update the bootloader settings. These live at address 0x7f000, and are part of the bootloader program. These may be revised at a later date, because this settings field is mostly useful for updating the SoftDevice that resides at the beginning of flash.

1. Attach openocd using ./swd and then telnet to localhost:4444
2. Run nrf51 mass_erase
3. Run program ../bootloader/_build/build-simmel/simmel_bootloader-0.3.2-56-g02b947e-nosd.hex
4. Run program ../bootloader/lib/softdevice/s140_nrf52_7.0.1/s140_nrf52_7.0.1_softdevice.hex
5. Run reset
6. Load firmware.uf2 via USB from Circuit Python.

Building Circuit Python (subsequent times)

Syncronize with the latest master. This will put you on a "detached head" state, meaning you're not on any particular branch.

git fetch origin           # Download the latest copy of all repositories to the git work area
git stash                  # If you've made changes, back them up here
git checkout origin master # Check out the latest master from the work area
git submodule sync         # If any submodule URLs have changed, update them
git submodule update       # Check out the latest submodules
git checkout -b mywork     # Exit `detached head` state and give it a new branch name

The process of building is the same:

cd ports/nrf               # Change to the NRF ports directory
rm -rf build-simmel        # Remove any existing directory -- this is important if the .ld file changes
make BOARD=simmel          # Build circuitpython

Loading Circuit Python

You can load build-simmel/firmware.elf via GDB, or load build-simmel/firmware.uf2 via the bootloader.