Port of Fredrik Stridsman's wall plotter to the ESP32

David Collins 79820e8fc2 Update README		4 years ago
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README.md	79820e8fc2 Update README	4 years ago

Stringent on ESP32

This is a port of Fredrik Stridsman's Arduino-based wall-plotter to the ESP32 microcontroller. (The original version was written for an Arduino Uno.)

Schematic

Please see the schematic below.

Voltage levels

There are two voltage rails:

5V for powering the motors
3.3V for powering the IR receiver and SD card.

Be careful to only supply 3.3V to your SD card and / or IR receiver. Otherwise there is a risk you could irreversibly damage them.

SD card (optional - NOT USED CURRENTLY)

Note: The SD card is not actually used in the current version of the firmware. The firmware uses the internal ESP32 filesystem instead (SPIFFS).

The SD card is used for storing plot files. Even if the plotter is controlled via the internet, the SD card could still be useful for downloading files before commencing the plot.

The SD card uses the standard SPI connections for the ESP32:

MOSI: GPIO 23
MISO: GPIO 19
SCK: GPIO 18

The chip-select (CS) pin on the SD card is connected to GPIO pin 22 on the ESP32.

Building the project

Step 1 - Install the ESP32 boards manager in Arduino IDE

In the Arduino IDE select 'File' -> 'Preferences'
Click on the icon beside 'Additional Board Managers URL'
Add the following URL: https://raw.githubusercontent.com/espressif/arduino-esp32/gh-pages/package_esp32_index.json
Click OK

Step 2 - Select board

In the 'Tools' Menu, open the 'Board' sub-menu
Select 'ESP32 Dev Module'

Step 3 - Install the required libraries

Install the following libraries using the 'Manage libraries' option in the 'Tools menu'.

ESP32Servo
IRremote

Step 4 - Build the project

Try to build the project and upload it to your ESP32 module.

Bluetooth control

This version of the firmware allows you to control the plotter via Bluetooth. Please see this document for more information.

Note: Only Android phones are supported for Bluetooth control. iPhones will not work (not currently at least).

More information

Fredrik has a lot more information in an article at: Project on hackster.io

README.md