Wiznet WizFi250 Manual

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Table of Contents
WizFi250 Programmer's Guide 1 .......................................................................................................................
Overview 1 .........................................................................................................................................................
AT Command Set 1 ...........................................................................................................................................
Responses 2 .....................................................................................................................................................
Command List 2 ...............................................................................................................................................
Basic Commands 3 ...........................................................................................................................................
WiFi Commands 3 ............................................................................................................................................
Network Commands 14 ....................................................................................................................................
Management Commands 20 ............................................................................................................................
Function Commands 35 ....................................................................................................................................
Command mode & Data mode 41 ....................................................................................................................
I/O PIN 42 ...........................................................................................................................................................
PIN Description 42 ............................................................................................................................................
FUNCTION Pin Usage 43 ...................................................................................................................................
How to Use Web Configuration 44 .................................................................................................................
Main Page 44 ....................................................................................................................................................
Serial to Wi-Fi Setting 45 ..................................................................................................................................
WPS(Push Button) 49 .......................................................................................................................................
WPS(PIN) 50 .....................................................................................................................................................
Change to OTA Mode 52 ...................................................................................................................................
GPIO Control 52 ................................................................................................................................................
Serial Setting 53 ...............................................................................................................................................
User Information Setting 54 .............................................................................................................................
How to Upgrade Firmware 55 .........................................................................................................................
Serial Line-APP+DCT 55 ...................................................................................................................................
Wi-Fi OTA(Over the Air) - APP 56 ......................................................................................................................
Firmware Recovery 61 .....................................................................................................................................
Examples - Association & Disassociation 62 ................................................................................................
Station Mode using WPA2 Static IP 62 ..............................................................................................................
Station Mode using WPA2 DHCP 62 ..................................................................................................................
AP Mode using WPA2 Static IP 63 .....................................................................................................................
Examples - Data Communication 64 ..............................................................................................................
Method of setting TCP Client and exchanging data in Data Mode 64 ...............................................................
Method of setting TCP Server and exchanging data in Data Mode 65 ..............................................................
Method of setting UDP Client and exchanging data in Data Mode 66 ..............................................................
Method of setting UDP Server and exchanging data in Data Mode 67 .............................................................
Method of setting TCP Client and exchanging data in Command Mode 68 ......................................................
Method of setting TCP Server and exchanging data in Command Mode 69 .....................................................
Method of setting UDP Client and exchanging data in Command Mode 69 ......................................................
Method of setting UDP Server and exchanging data in Command Mode 70 ....................................................
AT+SCON 71 ....................................................................................................................................................
Example of SSL Connection 73 .........................................................................................................................
Example of Multi Socket Connection 74 ...........................................................................................................
Air Command mode - WizFi250AirCmd 75 .......................................................................................................
Examples - WiFi Direct 77 ...............................................................................................................................
Appendix 80 .......................................................................................................................................................
WizFi250 UART Throughput Test Report 80 .....................................................................................................

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WizFi250 Programmer's Guide
Overview
This document provides programmers with all commands and explanations about WizFi250 control. Basically
programmers can control WizFi250 with commands set, known as AT command – the character string format. In
this document, we describe what AT commands are used, how each command operates and how programmers
have to handle those commands to get the expected response.
2013/09/04 12:11 · jeonggw
AT Command Set
This section provides a list of WizFi250 AT commands and their effects. Users can input commands and
parameters through USART line. Every command starts with the characters “AT”. Any other initial character will
cause an error in return. Commands and parameters are all ASCII characters, e.g. When you input
'AT+MMSG=1', you can input ASCII characters 'A', 'T', '+', 'M', 'M', 'S', 'G', '=', '1' and 'Enter Key' which should
be CR(0x0d), but neither CRLF(0x0d, 0x0a) nor LF(0x0a).
Some parameters are mandatory and the others are optional. (refer to Command Tables) Parameters must be
entered in an order of format column given by the command tables. Even though an optional parameter is not
used, the comma delimiters must still be included in the command. In most cases, valid commands return the
characters [OK]. Invalid inputs return [ERROR]. The possible responses sent by WizFi250 to the user side are
described at Responses. Below is a possible example which users can input. As you can see, WizFi250 return
“\r\n” back instead of “\r”, which means user (host system) always handle '\r\n' as a only delimiter.

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Input by User AT\r (0x61 0x74 0x0d)
Output from WizFi250 AT\r\n[OK]\r\n (0x0d 0x0a 0x5b 0x4f 0x4b 0x5d 0x0d 0x0a)
(* “AT\r\n” is Echo back of user input)
Responses
Responses are listed below.
Response Meaning
[OK] Command Request Success
[ERROR] Command Request Fail
[ERROR: INVALID INPUT] Wrong command or parameter
[ERROR: INVALID SCID] Wrong Socket ID
[ERROR: WiFi Status] Wrong WiFi Status (Some commands work only with Wi-Fi Joined status)
[ERROR: Mode Status] Wrong Mode Status (Some commands do not work in Data mode)
[CONNECT x] TCP Connection established & Socket Open
[DISCONNECT x] TCP Connection closed & Socket Close
[Link-Up Event] WiFi Connection was established
[Link-Down Event] WiFi Connection was closed
[Reset Event] System reset occurred (not by user)
2013/09/04 12:13 · jeonggw
Command List
Basic Commands
AT Terminal Check
WiFi Commands
AT+WJOIN WiFi Association
AT+WLEAVE WiFi Disassociation
AT+WSCAN WiFi Scan
AT+WSET WiFi Configuration
AT+WSEC WiFi Security Configuration
AT+WNET Network Configuration
AT+WSTAT Get Current WiFi Status
AT+WREG Country Configuration
AT+WWPS WiFi WPS Connection
AT+WANT WiFi Antenna Configuration
AT+WP2P_START Start WiFi Direct
AT+WP2P_STOP Stop WiFi Direct
AT+WP2P_PEERLIST Get WiFi Direct peer list
AT+WP2P_INVITE Invite WiFi Direct peer ID
AT+WCHECK Check Wi-Fi status using Ping
and Re-association with AP
Network Commands
AT+SCON Socket Open/Connect
Management Commands
AT+MPROF Profile Management
AT+MFDEF Perform Factory Reset
AT+MRESET Perform System Reset
AT+MMSG Set Message Print Level
AT+MMAC Set MAC Address
AT+MINFO Get System Information
AT+MECHO Set Echo Mode
AT+MHELP Print Command Description and
Usage
AT+MMCUPS MCU Power Save Enable/Disable
AT+MWIFIPS Wi-Fi Power Save Enable/Disable
AT+MCWUI Change WebServer User Information
AT+USET UART Configuration
AT+MSPI SPI Configuration
AT+MAIRCMD Air Command Configuration
AT+MEVTMSG Print [Listen x] as soon as it opens
up a socket through TCP server.
AT+MEVTFORM Event Message Form
Function Commands
AT+FPING PING Test

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Network Commands
AT+SMGMT Socket Management
AT+SSEND Data Send
AT+SDATA Return to Data Mode
AT+SFORM Define Data Receive Header Form
Function Commands
AT+FDNS DNS Query
AT+FWEBS Launch Web Server
AT+FGPIO GPIO Control
AT+FSOCK SOCKET Extension Option
AT+FOTA Launch OTA Mode
2013/09/04 14:50 · jeonggw
Basic Commands
Basic commands are listed below.
AT
Format:
AT
Meaning: Terminal Check
Check if AT Command Terminal is working.
Response:
[OK]
2013/09/04 12:14 · jeonggw
WiFi Commands
Commands related to WiFi are listed below.
AT+WJOIN
Format:
AT+WJOIN
Meaning: WiFi Association

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In the STA mode, it joins with the BSS selected by AT+WSET, AT+WSEC.
And in the AP mode, it starts to run as an Access Point.
There are 2 Wi-Fi modes in WizFi250, STA mode and SoftAP mode. When users execute AT+WJOIN
command, the current Wi-Fi mode works as the one previously selected by user input. It can be
selected or checked by AT+WSET and AT+WSEC commands, and it is the only way to handle Wi-Fi
mode.
SoftAP mode does not support WEP security method.
Response:
Joining : (SSID)
Successfully joined : (SSID)
[Link-Up Event]
IP Addr : xxx.xxx.xxx.xxx
Gateway : xxx.xxx.xxx.xxx
[OK]
Already Associated : (Mode)
[OK]
AT+WLEAVE
Format:
AT+WLEAVE
Meaning: WiFi Disassociation
In the STA mode, it leaves current BSS, but in the SoftAP mode, it stops to run as Access Point.
Response:
[Link-Down Event]
[OK]
[OK]

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AT+WSCANFormat:
AT+WSCAN=<SSID>,<BSSID>,<Channel>
Meaning: WiFi Scan
Return the scan results filtered by parameters.
<SSID>: SSID Filter (Optional)
Scan only the AP which has this SSID.
<BSSID>: BSSID Filter (Optional)
Scan only the AP which has this BSSID.
<Channel>: Channel Filter (Optional)
Scan only the AP in this Channel.
* When combining these filters, it works at the same time. For example, if you enter
AT+WSCAN=TestAP,00:08:DC:11:22:33', it only scans the AP which has TestAP as SSID and
00:08:DC:11:22:33 as BSSID in all the channel.
Examples)
AT+WSCAN=TestAP
AT+WSCAN=,,6
AT+WSCAN=,08:00:DC:11:22:33,11
Response:
Index/SSID/BSSID/RSSI(-dBm)/MaxDataRate(Mbps)/Security/RadioBand (GHz)/Channel
...
[OK]
AT+WSET
Format:
AT+WSET=<WiFiMode>,<SSID>,<BSSID>,<Channel>
Meaning: WiFi Configuration
<WiFiMode>: WiFi Mode to set (Required)
This changes current WiFi mode.
Parameter Meaning
0Set Wi-Fi mode as STA mode
1 Set Wi-Fi mode as AP mode
<SSID>: Target/Own SSID (Required, Max: 32 Character)

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Mode Meaning
STA The SSID of target AP
AP Its own SSID to run
<BSSID>: Target BSSID (Optional, Form: xx:xx:xx:xx:xx:xx)
Mode Meaning
STA The BSSID of target AP
AP Not used. if any, it will be ignored
<Channel>: Target/Own Channel (Optional)
Mode Meaning
STA In STA mode, the Channel of target AP
AP In AP mode, its own Channel to run (Default: 6)
* There are 2 Wi-Fi modes in WizFi250, STA mode and SoftAP mode. When users execute AT+WJOIN
command, it works as Wi-Fi mode previously selected by the user. It can be selected or checked by
AT+WSET and AT+WSEC commands, and it is the only way to handle Wi-Fi mode.
* AT+WSET, AT+WSEC commands save its parameters into the profile automatically, so the user does not
need to save the current profile.
Examples)
AT+WSET=0,WizFiAP
AT+WSET=0,WizFiAP,08:00:DC:11:22:33,1
Response:
[OK]
Format:
AT+WSET=?
Meaning: Get Current Setting
Response:
<WiFiMode>,<SSID>,<BSSID>,<Channel>
[OK]

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AT+WSECFormat:
AT+WSEC=<WiFiMode>,<SecType>,<Key>
Meaning: WiFi Security Configuration
<WiFiMode>: Target WiFi mode to set (Required)
Parameter Meaning
0Set Wi-Fi mode as STA mode
1 Set Wi-Fi mode as AP mode
<SecType>: Security type (Optional)
Parameter Meaning
OPEN None
WiFi Auto Security
WEP WEP (* Not support at SoftAP mode)
WPA WPA1 - TKIP
WPAAES WPA1 - AES
WPA2AES WPA2 - AES
WPA2TKIP WPA2 - TKIP
WPA2 WPA2 - Mixed
<Key>: Security key value
Method Length
WEP 5 or 13 (ASCII), 10 or 26 (HEX)
WPA 8 ~ 63 (ASCII), 128 (HEX)
* There are 2 Wi-Fi modes in WizFi250, STA mode and SoftAP mode. When users execute AT+WJOIN
command, it works as Wi-Fi mode previously selected by the user. It can be selected or checked by
AT+WSET and AT+WSEC commands, and it is the only way to handle Wi-Fi mode.
* AT+WSET, AT+WSEC commands save its parameters into the profile automatically, it works as Wi-Fi
mode previously selected by the user.
* Minimum key length is 8 bytes in WiFi Auto Security.
In case of WEP mode and 5 bytes key, you should input the key with HEX type.
AT+WSEC=0,,12345(X)
AT+WSEC=0,,3132333435(O)
In case of OPEN mode, you should input the 8 bytes dummy string. Then WizFi250 will ignore the dummy
key in OPEN mode.
AT+WSEC=0,,(X)
AT+WSEC=0,,12345678(O)
Examples)
AT+WSEC=0,WEP,12345
AT+WSEC=1,WPA2,12345678
AT+WSEC=0,,123456789
Response:

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[OK]
Format:
AT+WSEC=?
Meaning: Get Security Setting of Current Mode
Response:
<WiFiMode>,<SecType>,<Key>
[OK]
AT+WNET
Format:
AT+WNET=<DHCP>,<IP>,<SN>,<GW>
Meaning: Network Configuration
<DHCP>: DHCP On/Off (Optional)
Parameter Meaning
0DHCP Off, Static
1 DHCP On, DHCP Client
Mode Meaning
STA DHCP Client On/Off
AP Not used. if any, it will be ignored
<IP>: IP Address (Optional)
<SN>: Subnet Mask (Optional)
<GW>: Gateway Address (Optional)
Mode Meaning
STA AP(Router) gateway address
AP Not used. if any, it will be ignored
* When you turn DHCP On in STA Mode, <IP>,<SN>,<GW> are not needed. If you input them at this
time, they will be stored in the memory. They can be used later when set as Static(DHCP Off) without
inputting these parameters.
* In AP mode, DHCP Server will always run despite DHCP option, and Gateway option will not be used, So
both options will be ignored.

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Response:
[OK]
Format:
AT+WNET=?
Meaning: Get Current Network Setting
Note that <IP>,<SN>,<GW> address of response are not actual addresses, but addresses stored in the
memory. So when DHCP is on, it usually different from actual addresses.
Response:
<DHCP>,<IP>,<SN>,<GW>
[OK]
AT+WSTAT
Format:
AT+WSTAT
Meaning: Get Current WiFi Status
Response:
IF/SSID/IP-Addr/Gateway/MAC/TxPower(dBm)/RSSI(-dBm)
...
[OK]
AT+WREG
Format:
AT+WREG=<Country>

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Meaning: Country Configuration
Input a two letter country code (ISO 3166-1 A2) like US.
Response:
[OK]
Format:
AT+WREG=?
Meaning: Get Current Country Setting
Refer to ISO 3166-1 A2
Response:
<Country>
[OK]
AT+WWPS
Format:
AT+WWPS=<Mode>,<PinNum>
Meaning: WiFi WPS Connection
Join with an AP through WPS method
<Mode>: WPS Mode (Required)
Parameter Meaning
0WPS_PBC_MODE
1 WPS_PIN_MODE
<PinNum>: Pin Number (Pin Mode: Required, PBC Mode: N/A)
* The maximum pin number letter is 8.
Examples)
AT+WWPS=0

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AT+WWPS=1,12345670
Response:
[OK]
AT+WANT
Format:
AT+WANT=<Antenna type>
Meaning: WiFi Antenna Configuration
You had better not use this command unless it's absolutely necessary.
<Mode>: WiFi Antenna Type (Required)
Parameter Meaning
0u.FL Antenna
1 PCB Antenna
3 Auto Selection
Response:
[OK]
Format:
AT+WANT=?
Meaning: Get Current WiFi Antenna Type
Response:
<Antenna Type>
[OK]
AT+WP2P_START
Format:

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AT+WP2P_START
Meaning: Start WiFi Direct
Response:
STA MAC: CE:52:AF:C6:CF:B5
[OK]
AT+WP2P_STOP
Format:
AT+WP2P_STOP
Meaning: Stop WiFi Direct
Response:
[OK]
AT+WP2P_PEERLIST
Format:
AT+WP2P_PEERLIST
Meaning: Get WiFi Direct peer list
Response:
P2P Peers:
0: 'SHV-E250S' on channel 1
[OK]
AT+WP2P_INVITE
Format:
AT+WP2P_INVITE=<Peer ID>

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Meaning: Invite WiFi Direct peer ID
<Peer ID>: Peer ID to invite. This is from <AT+WP2P_PEERLIST> command.(Required)
Response:
[OK]
AT+WCHECK
Format:
AT+WCHECK=<time>,<ping try>,<ping error>
Meaning: Check Wi-Fi status using Ping and Re-association with AP
It must be set as service mode in order to use Re-association function.
This function only exist later vision of F/W 1.0.3.5.
To use this option, you must enter a non-zero value.
<time>: try to ping (to gateway) each time. 10 ~ 86400(required, unit:sec)
<ping try>: count of ping. 5 ~ 20(required, unit:number of times)
<ping error>: WizFi250 will be disassociated if ping timeout is more than this. 1 ~ 20(required,
unit:number of times)
Examples)
AT+WCHECK=0,0,0 (Not in use)
AT+WCHECK=60,5,3 (Recommended. WizFi250 will try to ping to the gateway every 60 seconds. If
ping timeout is more than 3, it would be disassociated.)
Response:
[OK]
AT+WADNS
Format:
AT+WADNS=<DNS Server1>,<DNS Server2>

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Meaning: Add DNS Server
<DNS Server 1>: DNS Server 1
<DNS Server 2>: DNS Server 2
Examples)
AT+WADNS=8.8.8.8
Response:
[OK]
2013/09/04 13:04 · jeonggw
Network Commands
Commands related to Network are listed below.
AT+SCON
Format:
AT+SCON=<OpenType>,<SocketType>,<RemoteIP>,<RemotePort>,<LocalPort>,<DataMode>
Meaning: Socket Open/Connect ( User can use max 8 sockets. )
Opens a socket and if it is a TCP Client, establishes TCP connection with remote peer device.
<OpenType>: Socket open type (Required)
Parameter Meaning
O open at Once
S register as a Service
SO open at Once & register as a Service
* AT ONCE: Assigns a socket immediately and if the socket is a TCP Client, tries to connect peer socket.
* AS SERVICE: Registers its information to the profile. When WiFi Joined, socket open/connect will be
performed automatically. If you want to use this after reset, It should be saved by using AT+MPROF=S
<SocketType>: Socket protocol to use (Required)
Parameter Meaning
TSN TCP Server Normal

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Parameter Meaning
TSS TCP Server Secured
TCN TCP Client Normal
TCS TCP Client Secured
USN UDP Server Normal
UCN UDP Client Normal
* 'Secured' means TCP connection through SSL Encryption.
* Actually, there is no Server/Client concept in UDP protocol. This concept is used to decide peer address
purposes. If a UDP Server receives any packet, its default peer address will be changed to the address of
the packet, so if you send data after that, it goes to the changed address. But If you use UDP Client, its
…default address stored by AT+SCON will never be changed.
<RemoteIP>: Remote IP address
Protocol Parameter Application
TCP Server N/A
TCP Client Required
UDP Server Optional
UDP Client Required
<RemotePort>: Remote port number
Same condition with upper, RemoteIP
<LocalPort>: Local port number (Required)
Local port number should not be duplicated with others which have opened before. When the value is 0,
in case the socket was a TCP/UDP Client, a random port number will be selected. If it was a TCP/UDP
Server, it will return an error message.
<DataMode>: Mode to run (Optional, default: 0)
Parameter Meaning
0Open as Command mode
1 Open as Data mode
* About Command/Data mode, refer to Command mode & Data mode
Examples)
AT+SCON=O,TSN,,,5000,0
AT+SCON=S,UCN,192.168.0.10,12345,5000,1 (Profile must be saved)
Response:
[OK]
Format:

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AT+SCON=?
Meaning: Get Previous Input Parameters
Use for check if previous input parameters are correct.
Response:
<OpenType>,<SocketType>,<RemoteIP>,<RemotePort>,<LocalPort>,<DataMode>
[OK]
AT+SMGMT
Format:
AT+SMGMT=<SocketID>
Meaning: Socket Management - Socket Close
Closes the selected socket and releases all its resources.
<SocketID>: Socket ID (Required)
Parameter Meaning
0 ~ 7 The socket ID to close
ALL All the opened sockets
* Opened socket information can be found by using '?' option.
Examples)
AT+SMGMT=5
AT+SMGMT=ALL
Response:
[OK]
Format:
AT+SMGMT=?

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Meaning: Socket Management - Get Opened Socket Status
This prints all of the opened sockets statuses.
Response:
Number of Sockets : x (SCID/Socket/Mode/Remote/Local/DataMode)
<SocketID>,<SocketAddr>,<SocketType>,<RemoteIP>,<RemotePort>,<LocalPort>,<Data
Mode>
...
[OK]
AT+SSEND
Format:
AT+SSEND=<SocketID>,<RemoteIP>,<RemotePort>,<SendSize>,<Timeout>
Meaning: Data Send
This is used only in command mode, not in data mode. It is not required in data mode as you can input
directly, but if you exit from data mode to command mode by inputting '+++', you can send data
through this command.
<SocketID>: Socket ID (Required)
<RemoteIP>: Remote IP Address
Protocol Parameter Application
TCP Server N/A
TCP Client N/A
UDP Server Optional
UDP Client Optional
* In case of TCP Server waiting for a client on listen state or in case of undecided remote address of the
UDP Server (meaning its remote address is 0.0.0.0:0), this command will fail.
<RemotePort>: Remote Port Number
Same condition with upper, RemoteIP
<SendSize>: Data size to send (Required)
Valid Range: 1 ~ 100,000,000 Byte
<Timeout >: Set timeout value (milliseconds unit) (Optional)
If the transmission takes time more time than timeout value, it will fail and return error response. Default
value is 10s + (100s / 1 MB)

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Examples)
AT+SSEND=0,,,3
AT+SSEND=1,192.168.0.100,5000,1000000,50000
Response:
[OK]
AT+SDATA
Format:
AT+SDATA
Meaning: Return to Data Mode
In data mode, it can be changed to command mode temporally by using serial '+++' input. After that, to
return to the data mode, you can use this command. If it is not data mode, [ERROR] response will be
returned.
Response:
[OK]
AT+SFORM
Format:
AT+SFORM=<Format>,<Start>,<Delim>,<End>,<Cls1>,<Cls2>
Meaning: Define Data Receive Header Form
Define the header of received data which is used at command mode. For example, default receiving
format look like below.
“{0,192.168.0.216,59834,5}hello(0xd)(0xa)”
This means ASCII code “hello” was received from 192.168.0.216:59834 by socket ID 0, and its length was
5. You can change this format to suit your system through this command. Factory default option is
“111111111,7B,2C,7D,0D,0A”
<Format>: Decide each of header items to use. (Required)

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If you want to set it to active, input '1', if not, input '0'.
Order Meaning
0Header Start
1 Socket ID
2 Delimiter
3 Remote IP Address
4 Remote Port Number
5 Data Length
6 Header End
7 Data End 1/2
8 Data End 2/2
* At default format, '{' '}' is header start and end, ',' is delimiter, 0xd,0xa is data end 1,2.
< Start>: Header Start Character (Required)
< Delim>: Delimiter Character (Required)
< End>: Header End Character (Required)
< Cls1>: Data End Character 1/2 (Required)
< Cls2>: Data End Character 2/2 (Required)
Examples)
AT+SFORM=111111111,7B,2C,7D,0D,0A
AT+SFORM=101100110,5B,2F,5D,0D,00
Response:
[OK]
Format:
AT+SFORM=?
Meaning: Get Current Data Receive Header Form
Response:
<Format>,<Start>,<Delim>,<End>,<Cls1>,<Cls2>
[OK]
AT+SOPT1
Format: