mirror of
https://github.com/esp8266/Arduino.git
synced 2025-06-04 18:03:20 +03:00
Ivan Grokhotkov
commit
17399b3c08
324
README.md
324
README.md
@ -1,308 +1,44 @@
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Arduino-compatible IDE with ESP8266 support
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===========================================
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[](https://travis-ci.org/igrr/Arduino)
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[](https://www.paypal.com/webscr?cmd=_s-xclick&hosted_button_id=4M56YCWV6PX66)
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This project brings support for ESP8266 chip to the Arduino environment. ESP8266WiFi library bundled with this project has the same interface as the WiFi Shield library, making it easy to re-use existing code and libraries.
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### Installing with Boards Manager ###
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Starting with 1.6.4, Arduino allows installation of third-party platform packages using Boards Manager. We have packages available for Windows, Mac OS, and Linux (32 and 64 bit).
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- Install Arduino 1.6.4 from the [Arduino website](http://www.arduino.cc/en/main/software).
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- Install Arduino 1.6.5 from the [Arduino website](http://www.arduino.cc/en/main/software).
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- Start Arduino and open Perferences window.
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- Enter ```http://arduino.esp8266.com/package_esp8266com_index.json``` into *Additional Board Manager URLs* field. You can add multiple URLs, separating them with commas.
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- Enter ```http://arduino.esp8266.com/stable/package_esp8266com_index.json``` into *Additional Board Manager URLs* field. You can add multiple URLs, separating them with commas.
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- Open Boards Manager from Tools > Board menu and install *esp8266* platform (and don't forget to select your ESP8266 board from Tools > Board menu after installation).
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### [Change log](hardware/esp8266com/esp8266/changes.md)
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#### Available versions
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##### Stable version 
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Boards manager link: `http://arduino.esp8266.com/stable/package_esp8266com_index.json`
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Documentation: [Reference](http://arduino.esp8266.com/stable/doc/reference.html)
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##### Staging version 
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Boards manager link: `http://arduino.esp8266.com/staging/package_esp8266com_index.json`
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Documentation: [Reference](http://arduino.esp8266.com/staging/doc/reference.html)
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### Building latest version from source [](https://travis-ci.org/igrr/Arduino)
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### Building latest version from source ###
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```
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$ git clone https://github.com/esp8266/Arduino.git
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$ cd Arduino/build
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$ ant dist
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```
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### Supported boards ###
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- Generic esp8266 modules (without auto-reset support)
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- NodeMCU
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- Olimex MOD-WIFI-ESP8266
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### Documentation ###
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Latest development version:
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### Things that work ###
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#### Basic Wiring functions ####
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```pinMode```, ```digitalRead```, ```digitalWrite```, ```analogWrite``` work as usual.
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Pin numbers correspond directly to the esp8266 GPIO pin numbers. To read GPIO2,
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call ```digitalRead(2);```
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GPIO0-GPIO15 can be ```INPUT```, ```OUTPUT```, ```INPUT_PULLUP```, and ```INPUT_PULLDOWN```.
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GPIO16 can be ```INPUT```, ```OUTPUT``` or ```INPUT_PULLDOWN```.
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```analogRead(A0)``` reads the value of the ADC channel connected to the TOUT pin.
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```analogWrite(pin, value)``` enables software PWM on the given pin. PWM may be used on pins 0 to 15.
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Call ```analogWrite(pin, 0)``` to disable PWM on the pin. ```value``` may be in range from 0 to ```PWMRANGE```, which is currently equal to 1023.
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Pin interrupts are supported through ```attachInterrupt```, ```detachInterrupt``` functions.
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Interrupts may be attached to any GPIO pin, except GPIO16. Standard Arduino interrupt
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types are supported: ```CHANGE```, ```RISING```, ```FALLING```.
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#### Pin Functions ####
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The most usable pin functions are mapped to the macro ```SPECIAL```, so calling ```pinMode(pin, SPECIAL)```
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will switch that pin in the most usable FUNCTION_X. Those are UART RX/TX on pins 1 - 3, HSPI for pins 12-15 and CLK functions for pins 0, 4 and 5.
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#### Timing and delays ####
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```millis``` and ```micros``` return the number of milliseconds and microseconds elapsed after reset, respectively.
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```delay``` pauses the sketch for a given number of milliseconds and allows WiFi and TCP/IP tasks to run.
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```delayMicroseconds``` pauses for a given number of microseconds.
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Remember that there is a lot of code that needs to run on the chip besides the sketch
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when WiFi is connected. WiFi and TCP/IP libraries get a chance to handle any pending
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events each time the ```loop()``` function completes, OR when ```delay(...)``` is called.
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If you have a loop somewhere in your sketch that takes a lot of time (>50ms) without
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calling ```delay()```, you might consider adding a call to delay function to keep the WiFi
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stack running smoothly.
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There is also a ```yield()``` function which is equivalent to ```delay(0)```. The delayMicroseconds
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function, on the other hand, does not yield to other tasks, so using it for delays
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more than 20 milliseconds is not recommended.
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#### Serial ####
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```Serial``` object works much the same way as on a regular Arduino. Apart from hardware FIFO (128 bytes for TX and RX) HardwareSerial has additional 256-byte TX and RX buffers. Both transmit and receive is interrupt-driven. Write and read functions only block the sketch execution when the respective FIFO/buffers are full/empty.
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```Serial``` uses UART0, which is mapped to pins GPIO1 (TX) and GPIO3 (RX). Serial may be remapped to GPIO15 (TX) and GPIO13 (RX) by calling ```Serial.swap();``` after ```Serial.begin();```. Calling ```swap``` again maps UART0 back to GPIO1 and GPIO3.
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```Serial1``` uses UART1 which is a transmit-only UART. UART1 TX pin is GPIO2. To use ```Serial1```, call ```Serial1.begin```.
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By default the diagnostic output from WiFi libraries is disabled when you call ```Serial.begin```. To enable debug output again, call ```Serial.setDebugOutput(true);```. To redirect debug output to ```Serial1``` instead, call ```Serial1.setDebugOutput(true);```.
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You also need to use ```Serial.setDebugOutput(true)``` to enable output from the Arduino ```printf()``` function.
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Both ```Serial``` and ```Serial1``` objects support 5, 6, 7, 8 data bits, odd (O), even (E), and no (N) parity, and 1 or 2 stop bits. To set the desired mode, call ```Serial.begin(baudrate, SERIAL_8N1);```, ```Serial.begin(baudrate, SERIAL_6E2);```, etc.
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#### Progmem ####
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The Program memory features work much the same way as on a regular Arduino; placing read only data and strings in read only memory and freeing heap for your application.
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The important difference is that on the esp8266 the literal strings are not pooled. This means that the same literal string defined inside a ```F("")``` and/or ```PSTR("")``` will take up space for each instance in the code. So you will need to manage the duplicate strings yourself.
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#### WiFi(ESP8266WiFi library) ####
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This is mostly similar to WiFi shield library. Differences include:
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- ```WiFi.mode(m)```: set mode to ```WIFI_AP```, ```WIFI_STA```, or ```WIFI_AP_STA```.
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- call ```WiFi.softAP(ssid)``` to set up an open network
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- call ```WiFi.softAP(ssid, password)``` to set up a WPA2-PSK network (password should be at least 8 characters)
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- ```WiFi.macAddress(mac)``` is for STA, ```WiFi.softAPmacAddress(mac)``` is for AP.
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- ```WiFi.localIP()``` is for STA, ```WiFi.softAPIP()``` is for AP.
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- ```WiFi.RSSI()``` doesn't work
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- ```WiFi.printDiag(Serial);``` will print out some diagnostic info
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- ```WiFiUDP``` class supports sending and receiving multicast packets on STA interface.
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When sending a multicast packet, replace ```udp.beginPacket(addr, port)``` with
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```udp.beginPacketMulticast(addr, port, WiFi.localIP())```.
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When listening to multicast packets, replace ```udp.begin(port)``` with
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```udp.beginMulticast(WiFi.localIP(), multicast_ip_addr, port)```.
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You can use ```udp.destinationIP()``` to tell whether the packet received was
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sent to the multicast or unicast address.
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Also note that multicast doesn't work on softAP interface.
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WiFiServer, WiFiClient, and WiFiUDP behave mostly the same way as with WiFi shield library.
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Four samples are provided for this library.
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You can see more commands here: [http://www.arduino.cc/en/Reference/WiFi](http://www.arduino.cc/en/Reference/WiFi)
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#### Ticker ####
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Library for calling functions repeatedly with a certain period. Two examples included.
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It is currently not recommended to do blocking IO operations (network, serial, file) from Ticker
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callback functions. Instead, set a flag inside the ticker callback and check for that flag inside the loop function.
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#### EEPROM ####
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This is a bit different from standard EEPROM class. You need to call ```EEPROM.begin(size)```
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before you start reading or writing, size being the number of bytes you want to use.
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Size can be anywhere between 4 and 4096 bytes.
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```EEPROM.write``` does not write to flash immediately, instead you must call ```EEPROM.commit()```
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whenever you wish to save changes to flash. ```EEPROM.end()``` will also commit, and will
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release the RAM copy of EEPROM contents.
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EEPROM library uses one sector of flash located at 0x7b000 for storage.
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Three examples included.
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#### I2C (Wire library) ####
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Wire library currently supports master mode up to approximately 450KHz.
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Before using I2C, pins for SDA and SCL need to be set by calling
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```Wire.begin(int sda, int scl)```, i.e. ```Wire.begin(0, 2);``` on ESP-01,
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else they default to pins 4(SDA) and 5(SCL).
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#### SPI ####
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SPI library supports the entire Arduino SPI API including transactions, including setting phase (CPHA).
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Setting the Clock polarity (CPOL) is not supported, yet (SPI_MODE2 and SPI_MODE3 not working).
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#### ESP-specific APIs ####
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APIs related to deep sleep and watchdog timer are available in the ```ESP``` object, only available in Alpha version.
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```ESP.deepSleep(microseconds, mode)``` will put the chip into deep sleep. ```mode``` is one of ```WAKE_RF_DEFAULT```, ```WAKE_RFCAL```, ```WAKE_NO_RFCAL```, ```WAKE_RF_DISABLED```. (GPIO16 needs to be tied to RST to wake from deepSleep.)
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```ESP.restart()``` restarts the CPU.
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```ESP.getFreeHeap()``` returns the free heap size.
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```ESP.getChipId()``` returns the ESP8266 chip ID as a 32-bit integer.
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Several APIs may be used to get flash chip info:
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```ESP.getFlashChipId()``` returns the flash chip ID as a 32-bit integer.
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```ESP.getFlashChipSize()``` returns the flash chip size, in bytes, as seen by the SDK (may be less than actual size).
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```ESP.getFlashChipSpeed(void)``` returns the flash chip frequency, in Hz.
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```ESP.getCycleCount()``` returns the cpu instruction cycle count since start as an unsigned 32-bit. This is useful for accurate timing of very short actions like bit banging.
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```ESP.getVcc()``` may be used to measure supply voltage. ESP needs to reconfigure the ADC
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at startup in order for this feature to be available. Add the following line to the top
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of your sketch to use ```getVcc```:
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```
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ADC_MODE(ADC_VCC);
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```
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TOUT pin has to be disconnected in this mode.
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Note that by default ADC is configured to read from TOUT pin using ```analogRead(A0)```, and
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```ESP.getVCC()``` is not available.
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#### OneWire (from https://www.pjrc.com/teensy/td_libs_OneWire.html) ####
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Library was adapted to work with ESP8266 by including register definitions into OneWire.h
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Note that if you already have OneWire library in your Arduino/libraries folder, it will be used
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instead of the one that comes with this package.
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#### mDNS responder (ESP8266mDNS library) ####
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Allows the sketch to respond to multicast DNS queries for domain names like "foo.local".
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Currently the library only works on STA interface, AP interface is not supported.
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See attached example and library README file for details.
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#### DNS server (DNSServer library) ####
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Implements a simple DNS server that can be used in both STA and AP modes. The DNS server currently supports only one domain (for all other domains it will reply with NXDOMAIN or custom status code). With it clients can open a web server running on ESP8266 using a domain name, not an IP address.
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See attached example for details.
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#### Servo ####
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This library exposes the ability to control RC (hobby) servo motors. It will support upto 24 servos on any available output pin. By defualt the first 12 servos will use Timer0 and currently this will not interfere with any other support. Servo counts above 12 will use Timer1 and features that use it will be effected.
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While many RC servo motors will accept the 3.3v IO data pin from a esp8266, most will not be able to run off 3.3v and will require another power source that matches their specifications. Make sure to connect the grounds between the esp8266 and the servo motor power supply.
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#### Other libraries (not included with the IDE)
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Libraries that don't rely on low-level access to AVR registers should work well. Here are a few libraries that were verified to work:
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- [arduinoWebSockets](https://github.com/Links2004/arduinoWebSockets) - WebSocket Server and Client compatible with esp8266 (RFC6455)
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- [aREST](https://github.com/marcoschwartz/aREST) REST API handler library.
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- [Blynk](https://github.com/blynkkk/blynk-library) - easy IoT framework for Makers (check out the [Kickstarter page](http://tiny.cc/blynk-kick)).
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- [DallasTemperature](https://github.com/milesburton/Arduino-Temperature-Control-Library.git)
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- [DHT11](https://github.com/adafruit/DHT-sensor-library) - Download latest v1.1.0 library and no changes are necessary. Older versions should initialize DHT as follows: ```DHT dht(DHTPIN, DHTTYPE, 15);```
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- [NeoPixel](https://github.com/adafruit/Adafruit_NeoPixel) - Adafruit's NeoPixel library, now with support for the ESP8266 (use version 1.0.2 or higher from Arduino's library manager).
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- [NeoPixelBus](https://github.com/Makuna/NeoPixelBus) - Arduino NeoPixel library compatible with esp8266. Use the "NeoPixelAnimator" branch for esp8266 to get HSL color support and more.
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- [PubSubClient](https://github.com/Imroy/pubsubclient) MQTT library by @Imroy.
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- [RTC](https://github.com/Makuna/Rtc) - Arduino Library for Ds1307 & Ds3231 compatible with esp8266.
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- [Souliss, Smart Home](https://github.com/souliss/souliss) - Framework for Smart Home based on Arduino, Android and openHAB.
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- [ST7735](https://github.com/nzmichaelh/Adafruit-ST7735-Library) - Adafruit's ST7735 library modified to be compatible with esp8266. Just make sure to modify the pins in the examples as they are still AVR specific.
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#### Upload via serial port ####
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Pick the correct serial port.
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You need to put ESP8266 into bootloader mode before uploading code.
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#### Power Supply ####
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For stable use of the ESP8266 a power supply with 3V3 and >= 250mA is required.
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* Note
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- using Power from USB to Serial is may unstable, they not deliver enough current.
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#### Serial Adapter ####
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There are many different USB to Serial adapters / boards.
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* Note
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- for full upload management you need RTS and DTR
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- the chip need to have 3V3 TTL (5V may damage the chip)
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- not all board have all pins of the ICs as breakout (check before order)
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- CTS and DSR are not useful for upload (they are Inputs)
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* Working ICs
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- FT232RL
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- CP2102
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- may others (drop a comment)
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#### Minimal hardware Setup for Bootloading and usage ####
|
||||
|
||||
ESPxx Hardware
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||||
| PIN | Resistor | Serial Adapter |
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| ------------- | -------- | -------------- |
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||||
| VCC | | VCC (3.3V) |
|
||||
| GND | | GND |
|
||||
| TX or GPIO2* | | RX |
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||||
| RX | | TX |
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||||
| GPIO0 | PullUp | DTR |
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| Reset* | | RTS |
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||||
| GPIO15* | PullDown | |
|
||||
| CH_PD | PullUp | |
|
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|
||||
* Note
|
||||
- GPIO15 is also named MTDO
|
||||
- Reset is also named RSBT or REST (adding PullUp improves the stability of the Module)
|
||||
- GPIO2 is alternative TX for the boot loader mode
|
||||
|
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###### esp to Serial
|
||||
|
||||
|
||||
#### Minimal hardware Setup for Bootloading only ####
|
||||
ESPxx Hardware
|
||||
|
||||
| PIN | Resistor | Serial Adapter |
|
||||
| ------------- | -------- | --------------- |
|
||||
| VCC | | VCC (3.3V) |
|
||||
| GND | | GND |
|
||||
| TX or GPIO2 | | RX |
|
||||
| RX | | TX |
|
||||
| GPIO0 | | GND |
|
||||
| Reset | | RTS* |
|
||||
| GPIO15 | PullDown | |
|
||||
| CH_PD | PullUp | |
|
||||
|
||||
* Note
|
||||
- if no RTS is used a manual power toggle is needed
|
||||
|
||||
#### Minimal hardware Setup for running only ####
|
||||
|
||||
ESPxx Hardware
|
||||
|
||||
| PIN | Resistor | Power supply |
|
||||
| ------------- | -------- | --------------- |
|
||||
| VCC | | VCC (3.3V) |
|
||||
| GND | | GND |
|
||||
| GPIO0 | PullUp | |
|
||||
| GPIO15 | PullDown | |
|
||||
| CH_PD | PullUp | |
|
||||
|
||||
###### minimal
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||||
|
||||
|
||||
###### improved stability
|
||||
|
||||
- [Reference](hardware/esp8266com/esp8266/doc/reference.md)
|
||||
- [Supported boards](hardware/esp8266com/esp8266/doc/boards.md)
|
||||
- [Change log](hardware/esp8266com/esp8266/doc/changes.md)
|
||||
|
||||
### Issues and support ###
|
||||
|
||||
@ -310,16 +46,24 @@ Forum: http://www.esp8266.com/arduino
|
||||
|
||||
Submit issues on Github: https://github.com/esp8266/Arduino/issues
|
||||
|
||||
### Contributing
|
||||
|
||||
For minor fixes of code and documentation, go ahead and submit a pull request.
|
||||
|
||||
Larger changes (rewriting parts of existing code from scratch, adding new functions to the core, adding new libraries) should generally be discussed [in the chat](https://gitter.im/esp8266/Arduino) first.
|
||||
|
||||
Feature branches with lots of small commits (especially titled "oops", "fix typo", "forgot to add file", etc.) should be squashed before opening a pull request. At the same time, please refrain from putting multiple unrelated changes into a single pull request.
|
||||
|
||||
### License and credits ###
|
||||
|
||||
Arduino IDE is based on Wiring and Processing. It is developed and maintained by the Arduino team. The IDE is licensed under GPL, and the core libraries are licensed under LGPL.
|
||||
Arduino IDE is developed and maintained by the Arduino team. The IDE is licensed under GPL.
|
||||
|
||||
This build includes an xtensa gcc toolchain, which is also under GPL.
|
||||
|
||||
Espressif SDK included in this build is under Espressif Public License.
|
||||
ESP8266 core includes an xtensa gcc toolchain, which is also under GPL.
|
||||
|
||||
Esptool written by Christian Klippel is licensed under GPLv2, currently maintained by Ivan Grokhotkov: https://github.com/igrr/esptool-ck.
|
||||
|
||||
ESP8266 core support, ESP8266WiFi, Ticker, ESP8266WebServer libraries were written by Ivan Grokhotkov, ivan@esp8266.com.
|
||||
Espressif SDK included in this build is under Espressif MIT License.
|
||||
|
||||
ESP8266 core files are licensed under LGPL.
|
||||
|
||||
[SPI Flash File System (SPIFFS)](https://github.com/pellepl/spiffs) written by Peter Andersson is used in this project. It is distributed under MIT license.
|
||||
|
||||
139
doc/boards.md
Normal file
139
doc/boards.md
Normal file
@ -0,0 +1,139 @@
|
||||
---
|
||||
title: Supported Hardware
|
||||
layout: page
|
||||
---
|
||||
|
||||
- [Adafruit HUZZAH ESP8266 (ESP-12)](#adafruit-huzzah-esp8266-esp-12)
|
||||
- [NodeMCU 0.9](#nodemcu-0-9)
|
||||
- [NodeMCU 1.0](#nodemcu-1-0)
|
||||
- [Olimex MOD-WIFI-ESP8266](#olimex-mod-wifi-esp8266)
|
||||
- [SweetPea ESP-210](#sweetpea-esp-210)
|
||||
- [Generic ESP8266 modules](#generic-esp8266-modules)
|
||||
|
||||
### Adafruit HUZZAH ESP8266 (ESP-12)
|
||||
|
||||
*TODO: add notes*
|
||||
|
||||
### NodeMCU 0.9 <a name="nodemcu-0-9"></a>
|
||||
|
||||
#### Pin mapping
|
||||
|
||||
Pin numbers written on the board itself do not correspond to ESP8266 GPIO pin numbers. Constants are defined to make using this board easier:
|
||||
|
||||
```C++
|
||||
static const uint8_t D0 = 16;
|
||||
static const uint8_t D1 = 5;
|
||||
static const uint8_t D2 = 4;
|
||||
static const uint8_t D3 = 0;
|
||||
static const uint8_t D4 = 2;
|
||||
static const uint8_t D5 = 14;
|
||||
static const uint8_t D6 = 12;
|
||||
static const uint8_t D7 = 13;
|
||||
static const uint8_t D8 = 15;
|
||||
static const uint8_t D9 = 3;
|
||||
static const uint8_t D10 = 1;
|
||||
```
|
||||
|
||||
If you want to use NodeMCU pin 5, use D5 for pin number, and it will be translated to 'real' GPIO pin 14.
|
||||
|
||||
### NodeMCU 1.0 <a name="nodemcu-1-0"></a>
|
||||
|
||||
*TODO: add notes*
|
||||
|
||||
### Olimex MOD-WIFI-ESP8266
|
||||
|
||||
*TODO: add notes*
|
||||
|
||||
### SweetPea ESP-210
|
||||
|
||||
*TODO: add notes*
|
||||
|
||||
### Generic ESP8266 modules
|
||||
|
||||
These modules come in different form factors and pinouts. See the page at ESP8266 community wiki for more info:
|
||||
[ESP8266 Module Family](http://www.esp8266.com/wiki/doku.php?id=esp8266-module-family).
|
||||
|
||||
Usually these modules have no bootstapping resistors on board, insufficient decoupling capacitors, no voltage regulator, no reset circuit, and no USB-serial adapter. This makes using them somewhat tricky, compared to development boards which add these features.
|
||||
|
||||
In order to use these modules, make sure to observe the following:
|
||||
|
||||
- **Provide sufficient power to the module.** For stable use of the ESP8266 a power supply with 3.3V and >= 250mA is required. Using the power available from USB to Serial adapter is not recommended, these adapters typically do not supply enough current to run ESP8266 reliably in every situation. An external supply or regulator along with filtering capacitors is preferred.
|
||||
|
||||
- **Connect bootstapping resistors** to GPIO0, GPIO2, GPIO15 according to the schematics below.
|
||||
|
||||
- **Put ESP8266 into bootloader mode** before uploading code.
|
||||
|
||||
### Serial Adapter
|
||||
|
||||
There are many different USB to Serial adapters / boards.
|
||||
|
||||
* Note
|
||||
- for full upload management you need RTS and DTR
|
||||
- the chip need to have 3.3V TTL (5V may damage the chip)
|
||||
- not all board have all pins of the ICs as breakout (check before order)
|
||||
- CTS and DSR are not useful for upload (they are Inputs)
|
||||
|
||||
* Working ICs
|
||||
- FT232RL
|
||||
- CP2102
|
||||
- CH340G
|
||||
- maybe others (drop a comment)
|
||||
|
||||
### Minimal Hardware Setup for Bootloading and Usage
|
||||
|
||||
ESPxx Hardware
|
||||
|
||||
| PIN | Resistor | Serial Adapter |
|
||||
| ------------- | -------- | -------------- |
|
||||
| VCC | | VCC (3.3V) |
|
||||
| GND | | GND |
|
||||
| TX or GPIO2* | | RX |
|
||||
| RX | | TX |
|
||||
| GPIO0 | PullUp | DTR |
|
||||
| Reset* | PullUp | RTS |
|
||||
| GPIO15* | PullDown | |
|
||||
| CH_PD | PullUp | |
|
||||
|
||||
* Note
|
||||
- GPIO15 is also named MTDO
|
||||
- Reset is also named RSBT or REST (adding PullUp improves the stability of the Module)
|
||||
- GPIO2 is alternative TX for the boot loader mode
|
||||
- **Directly connecting a pin to VCC or GND is not a substitute for a PullUp or PullDown resistor, doing this can break upload management and the serial console, instability has also been noted in some cases.**
|
||||
|
||||
### ESP to Serial
|
||||
|
||||
|
||||
#### Minimal Hardware Setup for Bootloading only ##
|
||||
ESPxx Hardware
|
||||
|
||||
| PIN | Resistor | Serial Adapter |
|
||||
| ------------- | -------- | --------------- |
|
||||
| VCC | | VCC (3.3V) |
|
||||
| GND | | GND |
|
||||
| TX or GPIO2 | | RX |
|
||||
| RX | | TX |
|
||||
| GPIO0 | | GND |
|
||||
| Reset | | RTS* |
|
||||
| GPIO15 | PullDown | |
|
||||
| CH_PD | PullUp | |
|
||||
|
||||
* Note
|
||||
- if no RTS is used a manual power toggle is needed
|
||||
|
||||
#### Minimal Hardware Setup for Running only ##
|
||||
|
||||
ESPxx Hardware
|
||||
|
||||
| PIN | Resistor | Power supply |
|
||||
| ------------- | -------- | --------------- |
|
||||
| VCC | | VCC (3.3V) |
|
||||
| GND | | GND |
|
||||
| GPIO0 | PullUp | |
|
||||
| GPIO15 | PullDown | |
|
||||
| CH_PD | PullUp | |
|
||||
|
||||
### Minimal
|
||||
|
||||
|
||||
### Improved Stability
|
||||
|
||||
@ -1,6 +1,8 @@
|
||||
# Change log
|
||||
---
|
||||
title: Change log
|
||||
---
|
||||
|
||||
|
||||
## Current version
|
||||
|
||||
### Core
|
||||
|
||||
@ -8,7 +10,7 @@
|
||||
|
||||
### Libraries
|
||||
|
||||
- ESP8266WebServer: add gzip streaming, fix sendContent behaviour,
|
||||
- ESP8266WebServer: add gzip streaming, fix sendContent behaviour,
|
||||
add setContentSize method.
|
||||
- ESP8266WiFi: add BSSID, channel, isHidden methods, fix AP/STA mode
|
||||
selection (#28).
|
||||
@ -31,8 +33,8 @@ May 22, 2015
|
||||
- Better connection handling in ESP8266WebServer.
|
||||
The server now sends Content-Length and Connection: close headers,
|
||||
then waits for the client to disconnect. By not closing the connection
|
||||
actively, server avoids TIME_WAIT TCP state, and TCP stack is able to
|
||||
release the memory immediately, without waiting for 2xMSL period.
|
||||
actively, server avoids TIME_WAIT TCP state, and TCP stack is able to
|
||||
release the memory immediately, without waiting for 2xMSL period.
|
||||
If the client doesn't disconnect in 2000ms, the server closes the connection
|
||||
actively.
|
||||
- Add Hash library, which has a function to calculate SHA1 hash.
|
||||
@ -45,4 +47,3 @@ May 22, 2015
|
||||
May 19, 2015
|
||||
|
||||
- Initial release of Boards Manager package for ESP8266 platform.
|
||||
|
||||
|
||||
1187
doc/esp12.svg
Normal file
1187
doc/esp12.svg
Normal file
File diff suppressed because it is too large
Load Diff
|
After Width: | Height: | Size: 51 KiB |
212
doc/reference.md
Normal file
212
doc/reference.md
Normal file
@ -0,0 +1,212 @@
|
||||
---
|
||||
title: Reference
|
||||
---
|
||||
|
||||
## Digital IO
|
||||
|
||||
Pin numbers in Arduino correspond directly to the ESP8266 GPIO pin numbers. `pinMode`, `digitalRead`, and `digitalWrite` functions work as usual, so to read GPIO2, call `digitalRead(2)`.
|
||||
|
||||
Digital pins 0—15 can be `INPUT`, `OUTPUT`, or `INPUT_PULLUP`.
|
||||
Pin 16 can be `INPUT`, `OUTPUT` or `INPUT_PULLDOWN`. At startup, pins are configured as `INPUT`.
|
||||
|
||||
Pins may also serve other functions, like Serial, I2C, SPI. These functions are normally activated by the corresponding library. The diagram below shows pin mapping for the popular ESP-12 module.
|
||||
|
||||
|
||||
|
||||
Digital pins 6—11 are not shown on this diagram because they are used to connect flash memory chip on most modules. Trying to use these pins as IOs will likely cause the program to crash.
|
||||
|
||||
Note that some boards and modules (ESP-12ED, NodeMCU 1.0) also break out pins 9 and 11. These may be used as IO if flash chip works in DIO mode (as opposed to QIO, which is the default one).
|
||||
|
||||
## Analog input
|
||||
|
||||
ESP8266 has a single ADC channel available to users. It may be used either to read voltage at ADC pin, or to read module supply voltage (VCC).
|
||||
|
||||
To read external voltage applied to ADC pin, use `analogRead(A0)`. Input voltage range is 0 — 1.0V.
|
||||
|
||||
To read VCC voltage, ADC pin must be kept unconnected. Additionally, the following line has to be added to the sketch:
|
||||
|
||||
```c++
|
||||
ADC_MODE(ADC_VCC);
|
||||
```
|
||||
|
||||
This line has to appear outside of any functions, for instance right after the `#include ` lines of your sketch.
|
||||
|
||||
## Analog output
|
||||
|
||||
`analogWrite(pin, value)` enables software PWM on the given pin. PWM may be used on pins 0 to 16.
|
||||
Call `analogWrite(pin, 0)` to disable PWM on the pin. `value` may be in range from 0 to `PWMRANGE`, which is currently equal to 1023.
|
||||
|
||||
Pin interrupts are supported through `attachInterrupt`, `detachInterrupt` functions.
|
||||
Interrupts may be attached to any GPIO pin, except GPIO16. Standard Arduino interrupt
|
||||
types are supported: `CHANGE`, `RISING`, `FALLING`.
|
||||
|
||||
|
||||
## Timing and delays
|
||||
`millis()` and `micros()` return the number of milliseconds and microseconds elapsed after reset, respectively.
|
||||
|
||||
`delay(ms)` pauses the sketch for a given number of milliseconds and allows WiFi and TCP/IP tasks to run.
|
||||
`delayMicroseconds(us)` pauses for a given number of microseconds.
|
||||
|
||||
Remember that there is a lot of code that needs to run on the chip besides the sketch
|
||||
when WiFi is connected. WiFi and TCP/IP libraries get a chance to handle any pending
|
||||
events each time the `loop()` function completes, OR when `delay` is called.
|
||||
If you have a loop somewhere in your sketch that takes a lot of time (>50ms) without
|
||||
calling `delay`, you might consider adding a call to `delay` function to keep the WiFi
|
||||
stack running smoothly.
|
||||
|
||||
There is also a `yield()` function which is equivalent to `delay(0)`. The `delayMicroseconds`
|
||||
function, on the other hand, does not yield to other tasks, so using it for delays
|
||||
more than 20 milliseconds is not recommended.
|
||||
|
||||
## Serial
|
||||
|
||||
`Serial` object works much the same way as on a regular Arduino. Apart from hardware FIFO (128 bytes for TX and RX) HardwareSerial has additional 256-byte TX and RX buffers. Both transmit and receive is interrupt-driven. Write and read functions only block the sketch execution when the respective FIFO/buffers are full/empty.
|
||||
|
||||
`Serial` uses UART0, which is mapped to pins GPIO1 (TX) and GPIO3 (RX). Serial may be remapped to GPIO15 (TX) and GPIO13 (RX) by calling `Serial.swap()` after `Serial.begin`. Calling `swap` again maps UART0 back to GPIO1 and GPIO3.
|
||||
|
||||
`Serial1` uses UART1, TX pin is GPIO2. UART1 can not be used to receive data because normally it's RX pin is occupied for flash chip connection. To use `Serial1`, call `Serial1.begin(baudrate)`.
|
||||
|
||||
By default the diagnostic output from WiFi libraries is disabled when you call `Serial.begin`. To enable debug output again, call `Serial.setDebugOutput(true)`. To redirect debug output to `Serial1` instead, call `Serial1.setDebugOutput(true)`.
|
||||
|
||||
You also need to use `Serial.setDebugOutput(true)` to enable output from `printf()` function.
|
||||
|
||||
Both `Serial` and `Serial1` objects support 5, 6, 7, 8 data bits, odd (O), even (E), and no (N) parity, and 1 or 2 stop bits. To set the desired mode, call `Serial.begin(baudrate, SERIAL_8N1)`, `Serial.begin(baudrate, SERIAL_6E2)`, etc.
|
||||
|
||||
## Progmem
|
||||
|
||||
The Program memory features work much the same way as on a regular Arduino; placing read only data and strings in read only memory and freeing heap for your application.
|
||||
The important difference is that on the ESP8266 the literal strings are not pooled. This means that the same literal string defined inside a `F("")` and/or `PSTR("")` will take up space for each instance in the code. So you will need to manage the duplicate strings yourself.
|
||||
|
||||
## WiFi(ESP8266WiFi library)
|
||||
|
||||
This is mostly similar to WiFi shield library. Differences include:
|
||||
|
||||
- `WiFi.mode(m)`: set mode to `WIFI_AP`, `WIFI_STA`, or `WIFI_AP_STA`.
|
||||
- call `WiFi.softAP(ssid)` to set up an open network
|
||||
- call `WiFi.softAP(ssid, password)` to set up a WPA2-PSK network (password should be at least 8 characters)
|
||||
- `WiFi.macAddress(mac)` is for STA, `WiFi.softAPmacAddress(mac)` is for AP.
|
||||
- `WiFi.localIP()` is for STA, `WiFi.softAPIP()` is for AP.
|
||||
- `WiFi.RSSI()` doesn't work
|
||||
- `WiFi.printDiag(Serial)` will print out some diagnostic info
|
||||
- `WiFiUDP` class supports sending and receiving multicast packets on STA interface.
|
||||
When sending a multicast packet, replace `udp.beginPacket(addr, port)` with
|
||||
`udp.beginPacketMulticast(addr, port, WiFi.localIP())`.
|
||||
When listening to multicast packets, replace `udp.begin(port)` with
|
||||
`udp.beginMulticast(WiFi.localIP(), multicast_ip_addr, port)`.
|
||||
You can use `udp.destinationIP()` to tell whether the packet received was
|
||||
sent to the multicast or unicast address.
|
||||
Also note that multicast doesn't work on softAP interface.
|
||||
|
||||
`WiFiServer`, `WiFiClient`, and `WiFiUDP` behave mostly the same way as with WiFi shield library.
|
||||
Four samples are provided for this library.
|
||||
You can see more commands here: [http://www.arduino.cc/en/Reference/WiFi](http://www.arduino.cc/en/Reference/WiFi)
|
||||
|
||||
## Ticker
|
||||
|
||||
Library for calling functions repeatedly with a certain period. Two examples included.
|
||||
|
||||
It is currently not recommended to do blocking IO operations (network, serial, file) from Ticker
|
||||
callback functions. Instead, set a flag inside the ticker callback and check for that flag inside the loop function.
|
||||
|
||||
## EEPROM
|
||||
|
||||
This is a bit different from standard EEPROM class. You need to call `EEPROM.begin(size)`
|
||||
before you start reading or writing, size being the number of bytes you want to use.
|
||||
Size can be anywhere between 4 and 4096 bytes.
|
||||
|
||||
`EEPROM.write` does not write to flash immediately, instead you must call `EEPROM.commit()`
|
||||
whenever you wish to save changes to flash. `EEPROM.end()` will also commit, and will
|
||||
release the RAM copy of EEPROM contents.
|
||||
|
||||
EEPROM library uses one sector of flash located at 0x7b000 for storage.
|
||||
|
||||
Three examples included.
|
||||
|
||||
## I2C (Wire library)
|
||||
|
||||
Wire library currently supports master mode up to approximately 450KHz.
|
||||
Before using I2C, pins for SDA and SCL need to be set by calling
|
||||
`Wire.begin(int sda, int scl)`, i.e. `Wire.begin(0, 2)` on ESP-01,
|
||||
else they default to pins 4(SDA) and 5(SCL).
|
||||
|
||||
## SPI
|
||||
|
||||
SPI library supports the entire Arduino SPI API including transactions, including setting phase (CPHA).
|
||||
Setting the Clock polarity (CPOL) is not supported, yet (SPI_MODE2 and SPI_MODE3 not working).
|
||||
|
||||
## ESP-specific APIs
|
||||
|
||||
APIs related to deep sleep and watchdog timer are available in the `ESP` object, only available in Alpha version.
|
||||
|
||||
`ESP.deepSleep(microseconds, mode)` will put the chip into deep sleep. `mode` is one of `WAKE_RF_DEFAULT`, `WAKE_RFCAL`, `WAKE_NO_RFCAL`, `WAKE_RF_DISABLED`. (GPIO16 needs to be tied to RST to wake from deepSleep.)
|
||||
|
||||
`ESP.restart()` restarts the CPU.
|
||||
|
||||
`ESP.getFreeHeap()` returns the free heap size.
|
||||
|
||||
`ESP.getChipId()` returns the ESP8266 chip ID as a 32-bit integer.
|
||||
|
||||
Several APIs may be used to get flash chip info:
|
||||
|
||||
`ESP.getFlashChipId()` returns the flash chip ID as a 32-bit integer.
|
||||
|
||||
`ESP.getFlashChipSize()` returns the flash chip size, in bytes, as seen by the SDK (may be less than actual size).
|
||||
|
||||
`ESP.getFlashChipSpeed(void)` returns the flash chip frequency, in Hz.
|
||||
|
||||
`ESP.getCycleCount()` returns the cpu instruction cycle count since start as an unsigned 32-bit. This is useful for accurate timing of very short actions like bit banging.
|
||||
|
||||
`ESP.getVcc()` may be used to measure supply voltage. ESP needs to reconfigure the ADC
|
||||
at startup in order for this feature to be available. Add the following line to the top
|
||||
of your sketch to use `getVcc`:
|
||||
|
||||
```c++
|
||||
ADC_MODE(ADC_VCC);
|
||||
```
|
||||
|
||||
TOUT pin has to be disconnected in this mode.
|
||||
|
||||
Note that by default ADC is configured to read from TOUT pin using `analogRead(A0)`, and
|
||||
`ESP.getVCC()` is not available.
|
||||
|
||||
## OneWire (from https://www.pjrc.com/teensy/td_libs_OneWire.html)
|
||||
|
||||
Library was adapted to work with ESP8266 by including register definitions into OneWire.h
|
||||
Note that if you already have OneWire library in your Arduino/libraries folder, it will be used
|
||||
instead of the one that comes with this package.
|
||||
|
||||
## mDNS and DNS-SD responder (ESP8266mDNS library)
|
||||
|
||||
Allows the sketch to respond to multicast DNS queries for domain names like "foo.local", and DNS-SD (service dicovery) queries.
|
||||
Currently the library only works on STA interface, AP interface is not supported.
|
||||
See attached example for details.
|
||||
|
||||
## SSDP responder (ESP8266SSDP)
|
||||
|
||||
SSDP is another service discovery protocol, supported on Windows out of the box. See attached example for reference.
|
||||
|
||||
## DNS server (DNSServer library)
|
||||
|
||||
Implements a simple DNS server that can be used in both STA and AP modes. The DNS server currently supports only one domain (for all other domains it will reply with NXDOMAIN or custom status code). With it clients can open a web server running on ESP8266 using a domain name, not an IP address.
|
||||
See attached example for details.
|
||||
|
||||
## Servo
|
||||
|
||||
This library exposes the ability to control RC (hobby) servo motors. It will support upto 24 servos on any available output pin. By defualt the first 12 servos will use Timer0 and currently this will not interfere with any other support. Servo counts above 12 will use Timer1 and features that use it will be effected.
|
||||
While many RC servo motors will accept the 3.3V IO data pin from a ESP8266, most will not be able to run off 3.3v and will require another power source that matches their specifications. Make sure to connect the grounds between the ESP8266 and the servo motor power supply.
|
||||
|
||||
## Other libraries (not included with the IDE)
|
||||
|
||||
Libraries that don't rely on low-level access to AVR registers should work well. Here are a few libraries that were verified to work:
|
||||
|
||||
- [arduinoWebSockets](https://github.com/Links2004/arduinoWebSockets) - WebSocket Server and Client compatible with ESP8266 (RFC6455)
|
||||
- [aREST](https://github.com/marcoschwartz/aREST) REST API handler library.
|
||||
- [Blynk](https://github.com/blynkkk/blynk-library) - easy IoT framework for Makers (check out the [Kickstarter page](http://tiny.cc/blynk-kick)).
|
||||
- [DallasTemperature](https://github.com/milesburton/Arduino-Temperature-Control-Library.git)
|
||||
- [DHT11](https://github.com/adafruit/DHT-sensor-library) - Download latest v1.1.0 library and no changes are necessary. Older versions should initialize DHT as follows: `DHT dht(DHTPIN, DHTTYPE, 15)`
|
||||
- [NeoPixel](https://github.com/adafruit/Adafruit_NeoPixel) - Adafruit's NeoPixel library, now with support for the ESP8266 (use version 1.0.2 or higher from Arduino's library manager).
|
||||
- [NeoPixelBus](https://github.com/Makuna/NeoPixelBus) - Arduino NeoPixel library compatible with ESP8266. Use the "NeoPixelAnimator" branch for ESP8266 to get HSL color support and more.
|
||||
- [PubSubClient](https://github.com/Imroy/pubsubclient) MQTT library by @Imroy.
|
||||
- [RTC](https://github.com/Makuna/Rtc) - Arduino Library for Ds1307 & Ds3231 compatible with ESP8266.
|
||||
- [Souliss, Smart Home](https://github.com/souliss/souliss) - Framework for Smart Home based on Arduino, Android and openHAB.
|
||||
- [ST7735](https://github.com/nzmichaelh/Adafruit-ST7735-Library) - Adafruit's ST7735 library modified to be compatible with ESP8266. Just make sure to modify the pins in the examples as they are still AVR specific.
|
||||
Loading…
x
Reference in New Issue
Block a user