EspPlug

This board is intended to allow direct interfacing between ESP8266 modules and your computer via the USB serial port.

Serial parameters

Default module settings are 9600,N,8,1 for older firmware versions and 115200,N,8,1 for newer.

Jumpers

JP1 and JP2 on the bottom of the board control GP0 pin of ESP8266 module. At most one jumper should be soldered at any time. If connected to GND, ESP8266 module will enter firmware update mode every time it is plugged in. If GP0 is connected to DTR#, firmware update can be programmatically controlled; i.e. when DTR is high, firmware update will be enabled and when DTR is low, normal operation will proceed. Both these jumpers can be left disconnected if firmware upgrade functionality is not needed.

Commands

All commands have prefix AT and have to end with .

AT

Replies with OK.

Example

AT

OK

ATEstate

Turn character echoing off (0) or on (1).

Echo will be turned on by default and every time device is reset.

state:

• 0 - Echo off
• 1 - Echo on

Example

ATE0

OK

AT+RST

Reset the module.

Example

AT+RST

OK
c_▒▒RS▒▒FjS▒fJ[▒▒▒
[Vendor:www.ai-thinker.com Version:0.9.2.4]

ready

AT+GMR

Shows the firmware version.

Example

AT+GMR
0018000902-AI03

OK

AT+CIUPDATE

Upgrades the firmware from cloud. Must be connected as client to access point with Internet access. Upgrade itself takes couple of minutes.

If firmware upgrade fails, at Electrodragon Blog you can see instructions for manual firmware update and a link to binaries needed for repair. To enter bootloader mode short between GP0 and GND will be needed (exposed on board's bottom as jumper link). Alternative firmwares and tools can be found on Electrodragon Documentation page.

Example

AT+CIUPDATE
+CIPUPDATE:1
+CIPUPDATE:2
+CIPUPDATE:3
+CIPUPDATE:4

OK

 ets Jan  8 2013,rst cause:4, boot mode:(3,6)

wdt reset
load 0x40100000, len 212, room 16
tail 4
chksum 0x5e
load 0x3ffe8000, len 788, room 4
tail 0
chksum 0x1c
load 0x3ffe8314, len 72, room 8
tail 0
chksum 0x55
csum 0x55
jump to user1
rN▒
ready

AT+CIOBAUD=rate

Changes baud rate.

Example

AT+CIOBAUD=115200
BAUD->115200

OK

AT+CIOBAUD?

Shows current baud rate.

Result is given as:

+CIOBAUD:rate

Example

AT+CIOBAUD?
+CIOBAUD:9600

OK

AT+CWMODE=mode

Changes the mode to one specified after the command.

mode:

• 1 - Client
• 2 - Access point
• 3 - Both client and access point

Example

AT+CWMODE=1

OK

AT+CWMODE?

Read current mode.

Result is given as:

+CWMODE:mode

mode:

• 1 - Client
• 2 - Access point
• 3 - Both client and access point

Example

AT+CWMODE?
+CWMODE:1

OK

AT+CWLAP

Shows visible networks. Only valid in client modes (1 and 3).

Results are given as multiple lines each formatted as:

+CWLAP:(security,"ssid",db,"mac",channel)

security:

• 0 - No authentication
• 1 - No authentication
• 2 - WEP
• 3 - WPA
• 4 - WPA2

Example

AT+CWLAP
+CWLAP:(3,"DIRECT-roku-374-F9AA61",-57,"40:a7:37:e0:32:a5",1)
+CWLAP:(4,"HOME-38C0",-93,"f4:32:c8:d0:38:c0",1)
+CWLAP:(0,"xfinitywifi",-90,"26:32:c8:d0:38:c2",1)
+CWLAP:(1,"kaostation",-86,"c0:1d:19:de:23:21",1)
+CWLAP:(4,"HOME-ACD0",-89,"a4:32:c8:cc:ac:d0",1)
+CWLAP:(3,"Prashant",-91,"e0:e5:2a:aa:65:66",1)
+CWLAP:(3,"Polaris",-47,"fc:ee:7b:30:a9:e8",1)
+CWLAP:(3,"Gost",-48,"ec:ee:7b:30:a9:e9",1)
+CWLAP:(0,"xfinitywifi",-90,"e6:32:c8:cc:ac:d2",1)
+CWLAP:(3,"NETGEAR",-82,"a0:22:3f:9f:f2:2a",2)
+CWLAP:(3,"kao",-88,"bc:22:0b:2f:e8:08",6)
+CWLAP:(4,"kao3",-85,"bc:22:0b:2f:e8:09",6)
+CWLAP:(3,"HOME-13C8",-94,"b0:26:f3:ab:13:c8",6)
+CWLAP:(0,"xfinitywifi",-89,"b6:32:c8:25:16:dc",1)
+CWLAP:(3,"NETGEAR21",-54,"64:94:fc:3f:6f:0c",11)
+CWLAP:(4,"HOME-4982",-83,"60:1a:ca:22:49:80",11)
+CWLAP:(4,"HOME-7A7F",-90,"3c:35:40:d2:7a:7f",1)
+CWLAP:(4,"150104",-92,"ac:35:40:67:65:79",1)

OK

AT+CWJAP

Join the network giving the SSID and password. Both should be enclosed in quotes.

Example

AT+CWJAP="Polaris","SomePassword"

OK

AT+CWJAP?

Shows joined network.

Result is given as:

+CWJAP:"ssid"

Example

AT+CWJAP?
+CWJAP:"Polaris"

OK

AT+CWQAP

Disconnects client from network.

Example

AT+CWQAP

OK

AT+CWSAP="ssid","password",channel,security

Set access point parameters. Valid only in AP modes (2 and 3).

channel is between 1 and 13.

security:

• 0 - No authentication
• 1 - WEP
• 3 - WPA
• 4 WPA2

Example

AT+CWSAP="Test","Password",1,0

AT+CWSAP?

Returns current access point parameters.

Result is given as:

+CWSAP:"ssid","password",channel,security

Example

AT+CWSAP?
+CWSAP:"ESP_9CB4F7","",1,0

OK

AT+CWLIF

Show access point clients.

Result is given as:

ip,mac

Example

AT+CWLIF
192.168.4.100,ac:f8:ae:51:89:07

OK

AT+CIFSR

Gives module IP address. First address given will be address in access point mode (2 or 3) while second address will be one used in client mode (1 or 3).

Results are given as list of:

ip

Example

AT+CIFSR
192.168.4.1
192.168.100.105

OK

AT+CIFSR (newer)

Returns IP address assigned to module in following format:

+CIFSR:STAIP,"ip" +CIFSR:STAMAC,"mac"

Example

AT+CIFSR
+CIFSR:STAIP,"192.168.200.126"
+CIFSR:STAMAC,"18:fe:34:9c:a4:aa"

OK

AT+CIPMUX=multi

Sets whether multiple connections are to be used.

multi:

• 0 - Single connection only
• 1 - Multiple connections enabled

Example

AT+CIPMUX=1

OK

AT+CIPMUX?

Returns whether multiple connections are supported.

Results are given as:

+CIPMUX:multi

multi:

• 0 - Single connection only
• 1 - Multiple connections enabled

Example

AT+CIPMUX?
+CIPMUX:0

AT+CIPSTATUS

Returns the status of the connection.

Result for server connection is given as:

STATUS:status

For client connection results are:

+CIPSTATUS:id,protocol,"ip",port,remoteport,status

status:

• 0 - Connected
• 2 - Listening
• 4 - Disconnected

Example

AT+CIPSTATUS
STATUS:4
+CIPSTATUS:0,"UDP","192.168.1.119",514,13566,0
+CIPSTATUS:2,"UDP","192.168.1.111",514,18867,0

OK

AT+CIPSTART="protocol",ip,port

Starts TCP or UDP connection in single connection mode.

protocol:

• UDP - User Datagram Protocol
• TCP - Transmission Control Protocol

Example (UDP)

AT+CIPSTART="UDP","192.168.1.119",514
0,CONNECT

OK

Example (TCP)

AT+CIPSTART="TCP","192.168.1.119",80
0,CONNECT

OK

AT+CIPSTART=id,"protocol",ip,port

Starts TCP or UDP connection in multiplexed mode.

protocol:

• UDP - User Datagram Protocol
• TCP - Transmission Control Protocol

Example

AT+CIPSTART=0,"UDP","192.168.1.119",514
0,CONNECT

OK

AT+CIPSEND=count

Sends number of characters over the connection.

Given characters can be inputed only after prompt (>) and command automatically completes as soon as enough characters are received.

Example

AT+CIPSEND=26
> ABCDEFGHIJKLMNOPQRSTUVWXYZ
SEND OK

AT+CIPSEND=id,count

Sends number of characters over the multiplexed connection.

Given characters can be inputed only after prompt (>) and command automatically completes as soon as enough characters are received.

Example

AT+CIPSEND=1,26
> ABCDEFGHIJKLMNOPQRSTUVWXYZ
SEND OK

AT+CIPCLOSE

Closes the connection.

Example

AT+CIPCLOSE
CLOSED

OK

AT+CIPCLOSE=id

Closes the connection in multiplexed mode.

Example

AT+CIPCLOSE=3
3,CLOSED

OK

AT+CIPSERVER=1,port

Starts TCP server on a given port. Multiplex mode must be turned on.

Example

AT+CIPSERVER=1,514

OK

AT+CIPSERVER=0

Closes TCP server connection. Module reset is needed after it.

Example

AT+CIPSERVER=0
we must restart

AT+CIPSTO=timeout

Sets server's connection timeout value. Value can only be set while server is listening.

Example

AT+CIPSTO=120

OK

AT+CIPSTO?

Returns currently set server timeout value.

Format is as follows:

+CIPSTO:timeout

Example

AT+CIPSTO?
+CIPSTO:180

OK

id,state

This is an unsolicited output that gets received every time there is a change on server connection.

state

• CONNECT - Connection established
• CLOSED - Connection closed

Example

0,CONNECT

+IPD

This is an unsolicited output that gets received every time server receives data.

Format:

+IPD,id,count:data

Example

+IPD,0,26:ABCDEFGHIJKLMNOPQRSTUVWXYZ
OK

Schematics

Manufacturing

If you want to make this board your self, just grab the latest gerbers and send them over to OSH Park (or any other PCB manufacturer of your choice).

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You can check my blog and other projects at www.jmedved.com.