===== Espressif ESP32 ===== [[https://espressif.com/en/products/hardware/esp32/resources|Dokumentation and Datasheet]]\\ [[https://leanpub.com/kolban-ESP32|Kolban's Book on ESP32]]\\ [[https://github.com/pcbreflux/espressif]]\\ {{:esp32:esp323_pinout_wroom_pinout.png?600|}}\\ ---- ===== Serial to USB Driver ===== - [[https://www.silabs.com/products/development-tools/software/usb-to-uart-bridge-vcp-drivers| SiLabs CP2104]]\\ - [[https://github.com/himalayanelixir/Arduino_USB_Drivers|CH340]]\\ ---- ==== Espressif ESP32 Development Board ==== The HW-607 ESP32 Board with a CH340G Serial to USB chip.\\ [[https://www.adafruit.com/product/3269|ESP32 Development Board]]\\ [[https://dl.espressif.com/doc/esp-idf/latest/get-started/get-started-devkitc.html]]\\

=== Upload a Sketch === The Examples for the ESP32 become visible after selecting **ESP32 DEV MODULE** in the Arduino IDE.\\ Set the flashing speed to 460800 or lower (115200).\\ Upload your sketch.\\ It could be necessary to start the IDE with administrator rights, too.\\ ---- === Special Hardware Configuration ==== ** The I/O pins are not 5V-tolerant! **\\ Use 3.3V instead.\\ \\ The build in LED is on GPIO 2.\\ \\ GPIO 34, 35, 36, 37, 38 and 39 are input only. And don't have a software pull-up or pull-down functions. One has to use an external 10k pull-up resistor.\\ \\ GPIO 6, 7, 8, 9, 10 and 11 are used for the SPI flash chip and can't be used for any other purposes.\\ ---- ==== WeMos ESP32 OLED Board ==== {{:esp32:ita4kni.jpg?600|}}\\ The OLED is connected like that:\\ pin5 - SDA pin4 - SCL The I2C address of the screen is 0x3c.\\ #include "SSD1306.h" SSD1306 display(0x3c, 5, 4); Librarie:\\ [[https://github.com/squix78/esp8266-oled-ssd1306]]\\ Board: ESP32 Dev Module Manuals:\\ [[http://www.instructables.com/id/ESP32-With-Integrated-OLED-WEMOSLolin-Getting-Star/]]\\ [[https://techtutorialsx.com/2017/12/02/esp32-arduino-interacting-with-a-ssd1306-oled-display/]]\\ ---- ==== Arduino core for ESP32 WiFi chip ==== [[https://github.com/espressif/arduino-esp32]]\\ Workaround for Arch Linux:\\ Install the latest Arduino IDE sudo pacman -S arduino Install Git sudo pacman -S git Download and run get-pip.py wget https://bootstrap.pypa.io/get-pip.py sudo python get-pip.py Install PySerial sudo pip install pyserial Make a folder in the Arduino folder sudo mkdir -p /usr/share/arduino/hardware/espressif cd /usr/share/arduino/hardware/espressif Download ESP32 and run get.py sudo git clone https://github.com/espressif/arduino-esp32.git esp32 cd esp32 sudo git submodule update --init --recursive cd tools sudo python2 get.py ---- ==== Programming the ESP32 ==== IO pin 34 and pin 35 don't work!\\ **ESP-IDF Programming Guide**\\ [[https://esp-idf.readthedocs.io/en/v2.0/index.html]]\\ **the 8bit DAC:**\\ [[https://esp-idf.readthedocs.io/en/v2.0/api/peripherals/dac.html]]\\ #include void setup() { } void loop() { for (int i=0; i<255; i++){ dac_out_voltage(DAC_CHANNEL_1, i); } } Output is a signal between 0 and 3.2V with 76Hz. ---- ==== Adafruit HUZZAH32 – ESP32 Feather Board ==== [[https://www.adafruit.com/product/3405|Adafruit HUZZAH32 – ESP32 Feather Board]]\\ [[https://learn.adafruit.com/adafruit-huzzah32-esp32-feather|Adafruit Learn Guid]]\\ ---- ===== DAC and ADC ===== **ADC**\\ analogRead(GPIO); analogReadResolution(resolution) //set the sample bits and resolution in bits, 9 => (0 – 511) and 12 => (0 – 4095), default 12 analogSetWidth(width) //set the sample bits and resolution analogSetCycles(cycles) //set the number of cycles per sample, range: 1 - 255, default 8 analogSetSamples(samples) //set the number of samples in the range, default is 1 sample analogSetClockDiv(attenuation) //set the divider for the ADC clock, range: 1 - 255, default is 1 analogSetAttenuation(attenuation) //sets the input attenuation for all ADC pins. Default is ADC_11db. Accepted values: ADC_0db: sets no attenuation (1V input = ADC reading of 1088). ADC_2_5db: sets an attenuation of 1.34 (1V input = ADC reading of 2086). ADC_6db: sets an attenuation of 1.5 (1V input = ADC reading of 2975). ADC_11db: sets an attenuation of 3.6 (1V input = ADC reading of 3959). analogSetPinAttenuation(pin, attenuation) //sets the input attenuation for the pin, default is ADC_11db adcAttachPin(pin) //attach a pin to ADC, returns TRUE or FALSE adcStart(pin) //starts an ADC conversion on attached pin’s bus adcBusy(pin) //check if conversion on the pin’s ADC bus is running, returns TRUE or FALSE adcEnd(pin) //get the result of the conversion: returns 16-bit integer taken from: [[https://www.malabdali.com/esp32-adc-and-dac/]] ---- **DAC**\\ The ESP32 has two DAC pins, GPIO25 and GPIO26. The resolution is 8 bits.\\ dacWrite(25, Value); // 255=3.3V 128=1.65V 0=0.0V For generating a sine wave one finds a good manual here: [[https://www.xtronical.com/basics/audio/dacs-on-esp32/|DAC’s on ESP32]]\\ ----