[submodule "components/esp_littlefs"]

path = components/esp_littlefs

url = https://github.com/joltwallet/esp_littlefs.git

This is an ESP-IDF project template running mruby on the ESP32 microcontroller.

for your operating system.

This has been tested on macOS and Ubuntu Linux, using

[ESP-IDF 5.1](https://github.com/espressif/esp-idf/tree/release/v5.1).

Recursively clone this repo to ensure the mruby (3.2.0) submodule gets downloaded:

The makefile configuration is in `main/component.mk`. The entry point source

file is `mruby_main.c`. Once that starts, it looks for `storage/main.rb` and runs it in mruby.

You can change the expected filename in `mruby_main.c`, or simply save your scripts as `main.rb`

inside the `storage` subfolder.

Your ESP32 should write 2 lines of numbers to the console.

The folder `main/examples` includes simple scripts demonstrating functionality.

Once you are familiar with the build process, try them with:

Replace `EXAMPLE_FILENAME` with one of the following:

* `simplest.rb` - Prints two strings

* `system.rb` - Demonstrates most system APIs

* `gpio.rb` - GPIO blink example

* `wifi_connect.rb` - Connects to WiFi

* `wifi_socket.rb` - Connects to WiFi and makes a TCPSocket connection

* `mqtt_publish.rb` - Connects to WiFi and publishes to MQTT broker

* `filesystem.rb` - Write/append/read a file on the virtual filesystem

* `ledc_breathe.rb` - Gradually fades the brightness of an LED up and down

* `ledc_buzzer.rb` - Plays a melody on a piezo-electric buzzer

* `ledc_servo.rb` - Controls position of a 180 degree hobby servo motor

**Note**: Edit GPIO numbers to match ones you are connected to, insert your WiFI credentials, customize MQTT settings etc.

There are multiple gems that can be turned on and off via the mruby

* [_mruby-socket_](https://github.com/mruby-esp32/mruby-socket/tree/0.5) - ESP32 Socket library (modified from mruby)

* [_mruby-esp32-system_](https://github.com/mruby-esp32/mruby-esp32-system/tree/0.5) - ESP32 system calls

* [_mruby-esp32-wifi_](https://github.com/mruby-esp32/mruby-esp32-wifi/tree/0.5) - ESP32 WiFi

* [_mruby-esp32-mqtt_](https://github.com/mruby-esp32/mruby-esp32-mqtt/tree/0.5) - ESP32 MQTT library

* [_mruby-esp32-gpio_](https://github.com/mruby-esp32/mruby-esp32-gpio/tree/0.5) - ESP32 GPIO library

* [_mruby-esp32-ledc_](https://github.com/mruby-esp32/mruby-esp32-ledc/tree/0.5) - ESP32 LEDC (PWM) library

To get gem changes to reflect in the build, `fullclean` the previous build, then build again:

All gems are enabled by default, so you can try out the examples, but it's a good idea to disable ones you don't need.

Everything works on:

- Original ESP32: `idf.py set-target esp32`

Everything except gpio gem works on:

- ESP32-S2: `idf.py set-target esp32s2`

- ESP32-S3: `idf.py set-target esp32s3`

If you followed the IDF installation instructions correctly for your chip,

you can switch the project target with the corresponding command above.

You will probably not be able to build again, until the project partition table is reset to `partitions.csv`. To do this:

The following files and folders are safe to delete when trying to solve build issues:

- `build`

- `components/mruby_component/build`

- `components/mruby_component/esp32_build_config.rb.lock`

- `managed_components`

- `dependencies.lock`

This project uses [littlefs](https://github.com/littlefs-project/littlefs) through IDF component

manager. If you see errors about files on disk changing, try deleting the last 2 items on this list.

REQUIRES esp_hw_support esp_rom esp_timer esp_wifi driver mqtt

PRIV_REQUIRES esp_hw_support esp_rom esp_timer esp_wifi driver mqtt

conf.gem :github => "mruby-esp32/mruby-io", :branch => '0.5'

conf.gem :github => "mruby-esp32/mruby-fileio", :branch => '0.5'

conf.gem :github => "mruby-esp32/mruby-socket", :branch => '0.5'

conf.gem :github => "mruby-esp32/mruby-esp32-system", :branch => '0.5'

conf.gem :github => "mruby-esp32/mruby-esp32-wifi", :branch => '0.5'

conf.gem :github => "mruby-esp32/mruby-esp32-mqtt", :branch => '0.5'

conf.gem :github => "mruby-esp32/mruby-esp32-gpio", :branch => '0.5'

conf.gem :github => "mruby-esp32/mruby-esp32-ledc", :branch => '0.5'

PRIV_REQUIRES nvs_flash esp_littlefs

littlefs_create_partition_image(storage ./storage FLASH_IN_PROJECT)

boot_count = nil

File.open('/storage/boot_count.txt', 'a+') { |f| boot_count = f.gets }

boot_count = 0 unless boot_count

boot_count = boot_count.to_i

boot_count += 1

File.open('/storage/boot_count.txt', 'w') { |f| f.puts(boot_count) }

puts "Boot count: #{boot_count}"

persistence_file = "/storage/test.txt"

if boot_count == 1

string1 = "testing "

string2 = "1,2,3..."

puts "Writing to #{persistence_file}: \"#{string1}#{string2}\""

File.open(persistence_file, 'w') { |f| f.write(string1) }

File.open(persistence_file, 'a') { |f| f.write(string2) }

print "Read from #{persistence_file}: "

File.open(persistence_file, 'r') { |f| f.each_line { |l| puts l } }

overwrite_file = '/storage/overwrite.txt'

File.open(overwrite_file, 'w') { |f| f.puts "12345678" }

File.open(overwrite_file, 'w') { |f| f.puts "1234" }

puts "#{overwrite_file} should contain: 1234"

print "#{overwrite_file} contains: "

File.open(overwrite_file, 'r') { |f| f.each_line { |l| puts l } }

group = ESP32::LEDC_LOW_SPEED_MODE

channel = ESP32::LEDC_CHANNEL_0

timer = ESP32::LEDC_TIMER_0

resolution = ESP32::LEDC_TIMER_8_BIT

frequency = 1000

pin = ESP32::GPIO::GPIO_NUM_2 # Built in LED on original ESP32 devkit.

ESP32::LEDC.timer_config(group, timer, resolution, frequency)

ESP32::LEDC.channel_config(pin, group, timer, channel)

loop do

i = 0

while (i < 256) do

ESP32::LEDC.set_duty(group, channel, i)

i += 1

ESP32::System.delay(10)

end

i=255

while (i > -1) do

ESP32::LEDC.set_duty(group, channel, i)

i -= 1

ESP32::System.delay(10)

end

group = ESP32::LEDC_LOW_SPEED_MODE

channel = ESP32::LEDC_CHANNEL_0

timer = ESP32::LEDC_TIMER_0

resolution = ESP32::LEDC_TIMER_8_BIT

pin = ESP32::GPIO::GPIO_NUM_4

ESP32::LEDC.channel_config(pin, group, timer, channel)

C4 = 262

D4 = 294

E4 = 330

notes = [

[E4, 1], [D4, 1], [C4, 1], [D4, 1], [E4, 1], [E4, 1], [E4, 2],

[D4, 1], [D4, 1], [D4, 2], [E4, 1], [E4, 1], [E4, 2],

[E4, 1], [D4, 1], [C4, 1], [D4, 1], [E4, 1], [E4, 1], [E4, 1], [E4, 1],

[D4, 1], [D4, 1], [E4, 1], [D4, 1], [C4, 4],

]

bpm = 180

beat_time = 60000.to_f / bpm

notes.each do |note|

# Set timer frequency to 0th element of the note array.

ESP32::LEDC.timer_config(group, timer, resolution, note[0])

# Duty cycle to 50% for square wave.

ESP32::LEDC.set_duty(group, channel, 128)

# Wait for length of the note, 1st element.

ESP32::System.delay(note[1] * beat_time)

# Duty cycle to 0 to stop note.

ESP32::LEDC.set_duty(group, channel, 0)