sphinx-key

You'll need a microSD card formatted using the FAT32 filesystem.
- On MacOS, go to Disk Utility.
- Click on the SDCard's disk in the left hand pane.
- Click on the Erase button on the cetner top toolbar.
- Then choose MS-DOS (FAT) for the format.
- Finally click on Erase, at the bottom right of the dialogue box.
Once you have the parts, solder the breakaway headers to the microSD card board as shown in the picture above.

Now follow the table below and the picture above to make all the connections:

SD card pin	ESP32-C3-DevKitM-1 v1.0	Notes
DO	GPIO2	Pin numbered 6 on board, same for the others below
CS	GPIO10	No need for any of the 10kOhm resistors mentioned in docs as of July 2022
SCK	GPIO6
DI	GPIO7
VCC	3V3
GND	GND

Software setup ( MacOS )

Make sure you have the Apple Command Line Developer tools installed on your machine. If not, run xcode-select --install
Install rust. You can grab the installation command at https://www.rust-lang.org/tools/install
Install brew. Get the installation command at https://brew.sh/
Install python3 and virtualenv. You can run brew install python3 virtualenv if necessary.
Run the following commands:

rustup install nightly
rustup component add rust-src --toolchain nightly
cargo install cargo-generate ldproxy espflash espmonitor

Hello World

Before we build and run the signer, we'll walk through a generic hello world to make sure the environment is all working:

Type cd ~. This places you in your home directory.
Run the command below, and set the following settings when prompted: Project Name=tiny-esp32, MCU=esp32c3, ESP-IDF native build version=v4.4, STD support=true, Configure project to use Dev Containers=false

cargo generate --vcs none --git https://github.com/esp-rs/esp-idf-template cargo

cd tiny-esp32
cargo build
Once the build is complete, run ls /dev/tty.* and note the files you see in that directory.
Plug in the ESP32-C3 dev board to your computer via Micro-USB, and again run ls /dev/tty.*. A new file should now appear, similar to this one /dev/tty.usbserial-1420
Run export FLASHPORT=[full file path noted in the previous step]. In my case: export FLASHPORT=/dev/tty.usbserial-1420
Now with the ESP32 dev board still plugged in, run:

espflash --monitor $FLASHPORT target/riscv32imc-esp-espidf/debug/tiny-esp32

This flashes the program onto the dev board, and then monitors the logs as soon as the program starts to run. By the end of execution, you should see a little Hello World log on your screen.
Do a ctrl-c to quit the monitor. You are now ready to build, flash, and run the signer :)

Signer

cd ~
git clone https://github.com/stakwork/sphinx-key.git
cd sphinx-key/sphinx-key
export CFLAGS=-fno-pic
export CC=$HOME/tiny-esp32/.embuild/espressif/tools/riscv32-esp-elf/*/riscv32-esp-elf/bin/riscv32-esp-elf-gcc
cargo build. You are now building the sphinx-key signer!
virtualenv venv
source venv/bin/activate
pip3 install --upgrade pip
pip3 install esptool
esptool.py --chip esp32-c3 elf2image target/riscv32imc-esp-espidf/debug/sphinx-key

Now flash the software onto the dev board using this command:

esptool.py --chip esp32c3 -p $FLASHPORT -b 460800 --before=default_reset --after=hard_reset write_flash --flash_mode dio --flash_freq 40m --flash_size 4MB 0x10000 target/riscv32imc-esp-espidf/debug/sphinx-key.bin

And then print the logs on your screen with this command:

espmonitor $FLASHPORT

Wait for the message Waiting for data from the phone!. The LED should blink green.
On your phone connect to the Wifi sphinxkey. This is served from the ESP32, and has no password.
Launch the signer setup flow on the sphinx app, and input the following settings:

ESP IP address: 192.168.71.1
Broker IP address and port: 44.198.193.18:1883
SSID: ssid of a local wifi with access to the internet
Password: password of the wifi from the previous step

Once the setup is complete, the message CONFIG SAVED should appear. Check in the log right above that all the settings are correct.
Press the RST button, to the right of the USB cable on the ESP. This does a hard reset of the ESP, and now launches the signer.
The LED will first blink yellow while it is connecting to the wifi.
When the signer is pinging for the broker, the LED on the ESP blinks purple.
On the logs, you should see BROKER IP AND PORT and LED STATUS: ConnectingToMqtt
Soon after, the LED should start to blink white, which means your signer is now connected to your node, and is ready for normal operation.

Launch the signer again

Run ls /dev/tty.* and note the files you see in that directory.
Plug in the ESP32-C3 dev board to your computer via Micro-USB, and again run ls /dev/tty.*. A new file should now appear, similar to this one /dev/tty.usbserial-1420
Run export FLASHPORT=[full file path noted in the previous step]. In my case: export FLASHPORT=/dev/tty.usbserial-1420
cd ~/sphinx-key/sphinx-key
export CFLAGS=-fno-pic
export CC=$HOME/tiny-esp32/.embuild/espressif/tools/riscv32-esp-elf/*/riscv32-esp-elf/bin/riscv32-esp-elf-gcc
cargo build. You are now building the sphinx-key signer!
source venv/bin/activate
esptool.py --chip esp32-c3 elf2image target/riscv32imc-esp-espidf/debug/sphinx-key Now flash the software onto the dev board using this command:

esptool.py --chip esp32c3 -p $FLASHPORT -b 460800 --before=default_reset --after=hard_reset write_flash --flash_mode dio --flash_freq 40m --flash_size 4MB 0x10000 target/riscv32imc-esp-espidf/debug/sphinx-key.bin

And then print the logs on your screen with this command:

espmonitor $FLASHPORT