NodeMCU Amica

NodeMCU Amica module.

Bottom side of the NodeMCU Amica module.

The nodeMCU Amica is a small module, which hosts an ESP8266 SOC (system-on-chip) on an ESP E-12 module. The Amica module has also a CP1202 USB-UART adapter on board, so that it is easy to communicate to the ESP8266 chip though the MicroUSB connector.

Additionally, the Amica module has an on-board LED, similar to the Arduino. But there are some differences about this LED:

1. The LED is not connected to pin 13 as on the Arduino UNO, but on the Amica module, the LED is connected to pin D0 (aka LED_BUILTIN, aka GPIO16) rather than to 13.
2. The LED is connected to + and not to GND, so you need to set the output to LOW in order to activate the LED.

So the blink example would look like this:

void setup() {
  pinMode(LED_BUILTIN, OUTPUT);     // Initialize the pin LED_BUILTIN (D0/GPIO16 on NodeMCU) as an output.
}
void loop() {
  digitalWrite(LED_BUILTIN, LOW);   // Turn the LED on (Active LOW)
  delay(1000);                      // Wait for a second
  digitalWrite(LED_BUILTIN, HIGH);  // Turn the LED off by making the voltage HIGH
  delay(1000);                      // Wait for two seconds (to demonstrate the active low LED)
}

Default Communication Settings

The modules usually come preloaded and configured with one of various firmwares:

Ai-Thinker (AT)

With this firmware, the module listens at a baud rate of 115200 bps (or older ones at 57600 bps) for commands in the shape of AT+... to establish WiFi, IP and TCP connections.

Example: (User input in bold.)

Ai-Thinker Technology Co.,Ltd.
 
ready
AT+CWMODE=1
 
OK
AT+CWJAP="CommonsLab","12345678"
WIFI CONNECTED
WIFI GOT IP  
 
OK
AT+CIFSR
+CIFSR:STAIP,"10.176.30.89"
+CIFSR:STAMAC,"18:fe:34:e2:0e:85"
 
OK

nodeMCU

With this firmware, the module listens at a baud rate of 9600 bps for commands in the Lua programming language.

Example: (User input in bold.)

NodeMCU 0.9.6 build 20150704  powered by Lua 5.1.4
> wifi.setmode(wifi.STATION)
> wifi.sta.config("TEST-AP","12345678")
> wifi.sta.connect()
> print(wifi.sta.getip())
10.176.30.118	255.255.255.192	10.176.30.65

Changing the Firmware

The module can be changed from the [http:// AT (Ai-Thinker) firmware] to the nodeMCU firmware and back or even to other firmware written in C with, for example, the Arduino IDE.

Flashing with Arduino IDE

You need to import the ESP boards into your Arduino IDE using the Board Manager by adding the link which is given at the Arduino core for ESP code repository. (Currently that is http://arduino.esp8266.com/stable/package_esp8266com_index.json)

Using the ESPtool directly

To write new firmware into the flash memory of the module, the Python script espTool can be used:

python esptool.py --port /dev/ttyUSB0  write_flash 0x00000 /Path/To/The/Firmware.bin

You might have to change /dev/ttyUSB0 to /dev/ttyUSB1 or similar.

List of AT commands (with AI-Thinker firmware)

(Based on info from ElectroDragon.) Baud rate at 115200 baud (older models at 57600) use option 'send new line' or 'carriage return' for each command.

	Set	Inquiry	Test	Execute
Syntax:	AT+<CommandGoesHere>=<…>	AT+<CommandGoesHere>?	AT+<CommandGoesHere>=?	AT+<CommandGoesHere>
Example:	AT+CWMODE=1	AT+CWMODE?	AT+CWMODE=?	-
Explanation:	Set the WiFi mode to Client	Check current mode	Return which modes supported	-

Command	Description	Type	Set/Execute	Inquiry	test	Parameters and Examples
AT	general test	basic	-	-	-	-
AT+RST	restart the module	basic	-	-	-	There must be no white space!
AT+GMR	check firmware version	basic	-	-	-	-
AT+CWMODE	wifi mode	wifi	AT+CWMODE=<mode>	AT+CWMODE?	AT+CWMODE=?	1= Sta, 2= AP, 3=both, Sta is the default mode of router, AP is a normal mode for devices
AT+CWJAP	join the AP	wifi	AT+CWJAP =<ssid>,< pwd >	AT+CWJAP?	-	ssid = ssid, pwd = wifi password
AT+CWLAP	list the AP	wifi	AT+CWLAP
AT+CWQAP	quit the AP	wifi	AT+CWQAP	-	AT+CWQAP=?
AT+CWSAP	set the parameters of AP	wifi	AT+CWSAP= <ssid>,<pwd>,<chl>, <ecn>	AT+ CWSAP?		ssid, pwd, chl = channel, ecn = encryption; eg. Connect to a WiFi Access-Point: AT+CWJAP="TEST-AP","12345678"; and then check if you are connected: AT+CWJAP?
AT+CWLIF	check join devices' IP	wifi	AT+CWLIF	-	-
AT+CIPSTATUS	get the connection status	TCP/IP	AT+CIPSTATUS			<id>,<type>,<addr>,<port>,<tetype>= client or server mode
AT+CIPSTART	set up TCP or UDP connection	TCP/IP	1: single connection (+CIPMUX=0) AT+CIPSTART= <type>,<addr>,<port>; 2: multiple connection (+CIPMUX=1) AT+CIPSTART= <id><type>,<addr>, <port>	-	AT+CIPSTART=?	id = 0-4, type = TCP/UDP, addr = IP address, port= port; eg. Connect to another TCP server, set multiple connection first: AT+CIPMUX=1; connect: AT+CIPSTART=4,"TCP","X1.X2.X3.X4",9999
AT+CIPMODE	set data transmission mode	TCP/IP	AT+CIPMODE=<mode>	AT+CIPSEND?		0: non-data mode, 1: data mode
AT+CIPSEND	send data	TCP/IP	1: single connection(+CIPMUX=0) AT+CIPSEND=<length>; 2: multiple connection (+CIPMUX=1) AT+CIPSEND= <id>,<length>		AT+CIPSEND=?	eg. send data: AT+CIPSEND=4,15 and then enter the data.
AT+CIPCLOSE	close TCP or UDP connection	TCP/IP	AT+CIPCLOSE=<id> or AT+CIPCLOSE		AT+CIPCLOSE=?
AT+CIFSR	Get IP address	TCP/IP	AT+CIFSR		AT+ CIFSR=?
AT+CIPMUX	set multiple connections	TCP/IP	AT+CIPMUX=<mode>	AT+CIPMUX?		0 for single connection 1 for multiple connections
AT+CIPSERVER	set as server	TCP/IP	AT+CIPSERVER= <mode>[,<port> ]			mode 0 to close server mode, mode 1 to open; port = port; eg. turn on as a TCP server: AT+CIPSERVER=1,8888, check the self server IP address: AT+CIFSR=?
AT+CIPSTO	Set the server timeout	TPC/IP	AT+CIPSTO=	AT+CIPSTO?		= 0..28800 seconds
+IPD	received data					For Single Connection mode(CIPMUX=0): + IPD, <len>: For Multi Connection mode(CIPMUX=1): + IPD, <id>, <len>: