Software
The files related to the WiFi PRO libraries are:
/WIFI_PRO/WaspWIFI_PRO.h
/WIFI_PRO/WaspWIFI_PRO.cpp
/WIFI_PRO/utility/ati_error_codes.h
/WIFI_PRO/utility/ati_generator.h
It is mandatory to include the WiFi PRO library when using this module. So the following line must be added at the beginning of the code:
#include <WaspWIFI_PRO.h>
To start using the Waspmote WiFi PRO library, an object from the ‘WaspWIFI_PRO’ class must be created. This object, called WIFI_PRO, is already created by default inside Waspmote WIFI_PRO library. It will be used through this guide to show how Waspmote works.
When using the class constructor, all variables are initialized to a default value.
The API constants used in functions are:
Constant | Description |
DEBUG_WIFI | This definition enables/disables the debug mode via USB port: 0: No debug mode enabled 1: debug mode enabled for error output messages 2: debug mode enabled for both error and OK messages |
WIFI_PRO_SCANFILE | This constant defines the file name where the scanned APs are stored |
WIFI_PRO_LISTFILE | This constant defines the file name where the FTP listed directories and files are stored |
OPEN | Security mode: no security enabled |
WEP64 | Security mode: WEP 64-bit security enabled |
WEP128 | Security mode: WEP 128-bit security enabled |
WPA | Security mode: WPA security enabled |
WPA2 | Security mode: WPA2 security enabled |
PROFILE_0PROFILE_1PROFILE_2PROFILE_3PROFILE_4PROFILE_5PROFILE_6PROFILE_7PROFILE_8PROFILE_9 | Profile definition for multiple SSIDs |
The variables used inside functions and Waspmote codes are:
Variable | Description |
_buffer | The buffer of memory used for storing the responses from the module |
_length | The useful length of the buffer |
_def_delay | The time to wait after sending every command until listen for a response |
_baudrate | The baud rate to be used when the module is switched on |
_uart | The selected UART (regarding the socket used: SOCKET0 or SOCKET1) |
_errorCode | It stores the error code returned by the module when calling a function with error response |
_rtt | It stores the last round trip time performed by a ping call |
_ip | It stores the module's IP address when the proper function is called |
_gw | It stores the gateway's IP address when the proper function is called |
_netmask | It stores the netmask's IP address when the proper function is called |
_dns1 | It stores the DNS #1 server's IP address when the proper function is called |
_dns2 | It stores the DNS #2 server's IP address when the proper function is called |
_socket_handle | It stores the handle number for a new TCP/UDP socket |
_ftp_handle | It stores the handle number for a new FTP session |
_filesize | It stores the FTP server file size when the proper function is called |
_essid | It stores the ESSID of the AP where the module is connected to |
_bssid | It stores the BSSID of the AP where the module is connected to |
_channel | It stores the channel used by the module in the current connection |
_rate | It stores the transmission rate used by the module in the current connection |
_level | It stores the signal level of the module in the current connection (%RSSI) |
_quality | It stores the link quality of the module in the current connection (%SNR) |
_snr | It stores the SNR of the module in the current connection (dBm) |
_power | It stores the transmission power level of the module (dBm) |
Through this guide there are lots of examples of using functions. In these examples, API functions are called to execute the commands, storing in their related variables the parameter value in each case. The functions are called using the predefined object
WIFI_PRO.All public functions return one of these possible values:
- 0: OK
- 1: ERROR. See corresponding error code
When a function returns error, the
_errorCode variable stores the corresponding error meaning. This error value is described by constants as the table below:Constant | Value | Error code description |
ERROR_CODE_0000 | 0 | Waspmote API timeout error |
ERROR_CODE_0010 | 10 | SD not present |
ERROR_CODE_0011 | 11 | SD file not created |
ERROR_CODE_0012 | 12 | SD error opening file |
ERROR_CODE_0013 | 13 | SD error setting file offset |
ERROR_CODE_0014 | 14 | SD error writing |
ERROR_CODE_0020 | 20 | RX buffer full |
ERROR_CODE_0021 | 21 | Error downloading UPGRADE.TXT |
ERROR_CODE_0022 | 22 | Filename in UPGRADE.TXT is not a 7-byte name |
ERROR_CODE_0023 | 23 | No FILE label is found in UPGRADE.TXT |
ERROR_CODE_0024 | 24 | NO_FILE is defined as FILE in UPGRADE.TXT |
ERROR_CODE_0025 | 25 | No PATH label is found in UPGRADE.TXT |
ERROR_CODE_0026 | 26 | No SIZE label is found in UPGRADE.TXT |
ERROR_CODE_0027 | 27 | No VERSION label is found in UPGRADE.TXT |
ERROR_CODE_0028 | 28 | Version indicated in UPGRADE.TXT is lower/equal to Waspmote's version |
ERROR_CODE_0029 | 29 | File size does not match the indicated in UPGRADE.TXT |
ERROR_CODE_0030 | 30 | Error downloading binary file |
ERROR_CODE_0031 | 31 | Invalid data length |
ERROR_CODE_0041 | 41 | Illegal delimiter |
ERROR_CODE_0042 | 42 | Illegal value |
ERROR_CODE_0043 | 43 | CR expected |
ERROR_CODE_0044 | 44 | Number expected |
ERROR_CODE_0045 | 45 | CR or ‘,’ expected |
ERROR_CODE_0046 | 46 | DNS expected |
ERROR_CODE_0047 | 47 | ‘:’ or ‘~’ expected |
ERROR_CODE_0048 | 48 | String expected |
ERROR_CODE_0049 | 49 | ‘:’ or ‘=’ expected |
ERROR_CODE_0050 | 50 | Text expected |
ERROR_CODE_0051 | 51 | Syntax error |
ERROR_CODE_0052 | 52 | ‘,’ expected |
ERROR_CODE_0053 | 53 | Illegal command code |
ERROR_CODE_0054 | 54 | Error when setting parameter |
ERROR_CODE_0055 | 55 | Error when getting parameter value |
ERROR_CODE_0056 | 56 | User abort |
ERROR_CODE_0061 | 61 | Internal memory failure |
ERROR_CODE_0062 | 62 | User aborted the system |
ERROR_CODE_0063 | 63 | CTSH needs to be LOW to change to hardware flow control |
ERROR_CODE_0064 | 64 | User aborted last command using ‘---’ |
ERROR_CODE_0065 | 65 | iChip unique ID already exists |
ERROR_CODE_0066 | 66 | Error when setting the MIF parameter |
ERROR_CODE_0067 | 67 | Command ignored as irrelevant |
ERROR_CODE_0068 | 68 | iChip serial number already exists |
ERROR_CODE_0069 | 69 | Timeout on host communication |
ERROR_CODE_0070 | 70 | Modem failed to respond |
ERROR_CODE_0071 | 71 | No dial tone response |
ERROR_CODE_0072 | 72 | No carrier modem response |
ERROR_CODE_0073 | 73 | Dial failed |
ERROR_CODE_0074 | 74 | WLAN connection lost |
ERROR_CODE_0075 | 75 | Access denied to ISP server |
ERROR_CODE_0086 | 86 | Writing to internal non-volatile parameters database failed |
ERROR_CODE_0087 | 87 | Web server IP registration failed |
ERROR_CODE_0088 | 88 | Socket IP registration failed |
ERROR_CODE_0094 | 94 | In Always Online mode, connection was lost and re-established |
ERROR_CODE_0096 | 96 | A remote host was disconnected |
ERROR_CODE_0100 | 100 | Error restoring default parameters |
ERROR_CODE_0101 | 101 | No ISP access numbers defined |
ERROR_CODE_0102 | 102 | No USRN defined |
ERROR_CODE_0103 | 103 | No PWD entered |
ERROR_CODE_0104 | 104 | No DNS defined |
ERROR_CODE_0111 | 111 | Serial data overflow |
ERROR_CODE_0112 | 112 | Illegal command when modem online |
ERROR_CODE_0116 | 116 | Error parsing a new trusted CA certificate |
ERROR_CODE_0117 | 117 | Error parsing a new Private Key |
ERROR_CODE_0118 | 118 | Protocol specified in the USRV parameter does not exist or is unknown |
ERROR_CODE_0119 | 119 | WPA passphrase too short has to be 8-63 chars |
ERROR_CODE_0125 | 125 | Invalid WEP key |
ERROR_CODE_0126 | 126 | Invalid parameters’ profile number |
ERROR_CODE_0128 | 128 | Product ID already exists |
ERROR_CODE_0129 | 129 | HW pin can not be changed after Product-ID was set |
ERROR_CODE_0200 | 200 | Socket does not exist |
ERROR_CODE_0201 | 201 | Socket empty on receive |
ERROR_CODE_0202 | 202 | Socket not in use |
ERROR_CODE_0203 | 203 | Socket down |
ERROR_CODE_0204 | 204 | No available sockets |
ERROR_CODE_0206 | 206 | PPP open failed for socket |
ERROR_CODE_0207 | 207 | Error creating socket |
ERROR_CODE_0208 | 208 | Socket send error |
ERROR_CODE_0209 | 209 | Socket receive error |
ERROR_CODE_0210 | 210 | PPP down for socket |
ERROR_CODE_0212 | 212 | Socket flush error |
ERROR_CODE_0215 | 215 | No carrier error on socket operation |
ERROR_CODE_0216 | 216 | General exception |
ERROR_CODE_0217 | 217 | Out of memory |
ERROR_CODE_0218 | 218 | An STCP (Open Socket) command specified a local port number that is already in use |
ERROR_CODE_0220 | 220 | SSL initialization/internal CA certificate loading error |
ERROR_CODE_0221 | 221 | Illegal SSL socket handle. Must be an open and active TCP socket |
ERROR_CODE_0222 | 222 | Trusted CA certificate does not exist |
ERROR_CODE_0224 | 224 | Decoding error on incoming SSL data |
ERROR_CODE_0225 | 225 | No additional SSL sockets available |
ERROR_CODE_0226 | 226 | Maximum SSL packet size (2KB) exceeded |
ERROR_CODE_0227 | 227 | Send command failed because size of stream sent exceeded 2048 bytes |
ERROR_CODE_0228 | 228 | Send command failed because checksum calculated does not match checksum sent by host |
ERROR_CODE_0229 | 229 | SSL parameters are missing |
ERROR_CODE_0230 | 230 | Maximum packet size (4 GB) exceeded |
ERROR_CODE_0300 | 300 | HTTP server unknown |
ERROR_CODE_0301 | 301 | HTTP server timeout |
ERROR_CODE_0303 | 303 | No URL specified |
ERROR_CODE_0304 | 304 | Illegal HTTP host name |
ERROR_CODE_0305 | 305 | Illegal HTTP port number |
ERROR_CODE_0306 | 306 | Illegal URL address |
ERROR_CODE_0307 | 307 | URL address too long |
ERROR_CODE_0400 | 400 | MAC address exists |
ERROR_CODE_0401 | 401 | No IP address |
ERROR_CODE_0402 | 402 | Wireless LAN power set failed |
ERROR_CODE_0403 | 403 | Wireless LAN radio control failed |
ERROR_CODE_0404 | 404 | Wireless LAN reset failed |
ERROR_CODE_0405 | 405 | Wireless LAN hardware setup failed |
ERROR_CODE_0406 | 406 | Command failed because WiFi module is currently busy |
ERROR_CODE_0407 | 407 | Illegal WiFi channel |
ERROR_CODE_0408 | 408 | Illegal SNR threshold |
ERROR_CODE_0409 | 409 | WPA connection process has not yet completed |
ERROR_CODE_0410 | 410 | The network connection is offline (modem) |
ERROR_CODE_0411 | 411 | Command is illegal when Bridge mode is active |
ERROR_CODE_0501 | 501 | Communications platform already active |
ERROR_CODE_0505 | 505 | Cannot open additional FTP session – all FTP handles in use |
ERROR_CODE_0506 | 506 | Not an FTP session handle |
ERROR_CODE_0507 | 507 | FTP server not found |
ERROR_CODE_0508 | 508 | Timeout when connecting to FTP server |
ERROR_CODE_0509 | 509 | Failed to login to FTP server (bad username or password or account) |
ERROR_CODE_0510 | 510 | FTP command could not be completed |
ERROR_CODE_0511 | 511 | FTP data socket could not be opened |
ERROR_CODE_0512 | 512 | Failed to send data on FTP data socket |
ERROR_CODE_0513 | 513 | FTP shutdown by remote server |
ERROR_CODE_0570 | 570 | PING destination not found |
ERROR_CODE_0571 | 571 | No reply to PING request |
The
ON() function allows to switch on the WiFi PRO module and it opens the MCU's UART for communicating with the module. After this step the module will be able to receive commands to manage it. It is necessary to indicate the socket that it is being used: SOCKET0 or SOCKET1.Example of use for SOCKET0:
{
WIFI_PRO.ON(SOCKET0);
}
The
resetValues() function allows to restore the module's non-volatile parameter database values to factory defaults. Each one of the module's non-volatile parameters has an associated default value. This function restores all parameters to their factory default values.Example of use:
{
WIFI_PRO.resetValues();
}
The
OFF() function allows the user to switch off the WiFi PRO module and close the UART. This function must be called in order to keep battery level when the module is not going to be used. It is necessary to indicate the socket that it is being used: SOCKET0 or SOCKET1.Example of use for SOCKET0:
{
WIFI_PRO.OFF(SOCKET0);
}
In order to configure the module to join an Access Point (AP), it is mandatory to define the ESSID of the AP, the password of the security enabled in that link and finally perform a software reset so as to apply the changes.
Once these parameters have been set, they are permanently stored in the non-volatile memory of the module. So, it is not necessary to re-configure these parameters anymore, unless the user needs to change the AP settings.
The
setESSID() function allows the user to configure the ESSID to join.The
getESSID() function allows the user to request the current ESSID setting. The _essid attribute permits to read the settings of the module.Example of use:
{
WIFI_PRO.setESSID(“libelium_AP”);
WIFI_PRO.getESSID();
}
Related variable:
WIFI_PRO._essid → Stores the current ESSID of the moduleThe
setPassword() function allows the user to configure the password to the module. It takes several seconds to generate the keys. This function needs two inputs:- Authentication mode:
OPEN: No securityWEP64: WEP 64-bitWEP128: WEP 128-bitWPA: WPA-PSKWPA2: WPA2-PSK
- Password:
- If Security Mode = WPA/WPA2: This is the pass-phrase to be used in generating the PSK encryption key. The allowed value for pass is an ASCII string containing 8 to 63 characters.
- If Security Mode = WEP64: This key must be defined by 10 hexadecimal digits. Each byte of the 5-byte key is defined by two ASCII characters in the ranges ['0' to '9'], ['A' to 'F'] or ['a' to 'f'].
- If Security Mode = WEP128: This key must be defined by 26 hexadecimal digits. Each byte of the 13-byte key is defined by two ASCII characters in the ranges ['0' to '9'], ['A' to 'F'] or ['a' to 'f'].
Example of use:
{
WIFI_PRO.setPassword(WPA2, “password”);
}
Once the module has been set to the correct settings they are kept in the non volatile memory of the module. Besides, it is mandatory to restart the module in order to force the module to use the new settings. For that purpose, the
softReset() function is used to perform a software reset to the module. After calling this function, the new setting takes effect.Once the module has valid settings in the non volatile memory, it automatically starts searching to join the Access Point. The
isConnected() function permits to know if the WiFi PRO module is already connected to the Access Point. This function returns true or false values in order to provide the status information.Examples of configuring the module and joining the AP:
When joining an AP it is possible to use the DHCP client of the module or configure a static IP address.
By default, the WiFi PRO module uses the DHCP client, so when it joins the AP, an IP address is assigned to the module. The
getIP() function permits to request the current IP address of the module.Example of use:
{
WIFI_PRO.getIP();
}
Related variable:
WIFI_PRO._ip → Stores the current IP address assigned to the moduleExample of getting the module's IP address:
It is possible to set up a default IP address for the WiFi PRO module. Besides, it is possible to set other network parameters: DNS address, Gateway address and Netmask. The functions for all these settings are shown below:
The
setIP() function allows the user to set the IP address to the module in the network.The
setDNS() function allows the user to set the DNS address to the WiFi PRO module.The
setGateway() function allows the user to set the Gateway address to the WiFi PRO module.The
setNetmask() function allows the user to set the netmask address to the WiFi PRO module.Remember that a software reset is needed in order to apply all these changes in the WiFi PRO module.
Example of use:
{
WIFI_PRO.setIP(“192.168.5.248”);
WIFI_PRO.setDNS(“8.8.8.8”);
WIFI_PRO.setGateway(“192.168.1.2”);
WIFI_PRO.setNetmask(“255.255.128.0”);
}
Example of using static IP address:
The
ping() function sends a two-byte ICMP PING request packet to the remote host defined as input argument. The input of the function can be a logical name of the target host or a host IP address. Upon successfully receiving an ICMP PING reply from the host, the round trip time in milliseconds is returned (RTT) and stored in the _rtt attribute.Example of use:
{
WIFI_PRO.ping(“www.google.com”);
}
Related variable:
WIFI_PRO._rtt → Stores the last round trip time performed by a ping callExample of performing a ping from the module:
The
setPower() function allows the user to configure the transmission power of the chipset. The getPower() function allows the user to request the transmission power of the chipset which is stored in the _power attribute. After a hardware or software reset, the power level parameter returns to its default value. This parameter is in the range 1 to 14 dBm. The default value is 14 dBm.Example of use:
{
WIFI_PRO.setPower(14);
WIFI_PRO.getPower();
}
Related variable:
WIFI_PRO._power → Stores the power level settingExample of setting the transmission power level:
Secure Sockets Layer (SSL) technology provides data encryption, server authentication and message integrity for a TCP/IP connection. The server authenticates the client using the client’s Public Key Certificate (PKC). So, it will be necessary to install the corresponding certificate, created by a CA (Certification Authority), to the module. These CA certificates are usually provided by the browsers.
For more information, refer to the tutorial related to SSL connections:
The
setCA() function sets the certificate of the trusted certificate authority. The WiFi PRO module accepts a server’s identity only if its certificate is signed by one of these certificate authorities.The certificate is a PEM format X509 certificate (DER format, Base-64 encoded with header and footer lines). The certificate is referenced as the trusted certificate authority’s certificate during SSL socket connection establishment (handshake). The WiFi PRO module establishes an SSL socket connection only to servers having a certificate authenticated by this certificate authority. The certificate must be defined by multiple lines separated by <CR>, beginning with:
-----BEGIN CERTIFICATE----- and terminating with: -----END CERTIFICATE-----. The certificate should include an RSA encryption public key of 1024 or 2048 bits. The signature algorithm may be MD2, MD5 or SHA1. The maximum size of the certificate is 1500 characters.Example of valid certificate setting:
{
char TRUSTED_CA[] =\
"-----BEGIN CERTIFICATE-----\r"\
"MIICPDCCAaUCEHC65B0Q2Sk0tjjKewPMur8wDQYJKoZIhvcNAQECBQAwXzELMAkG\r"\
"A1UEBhMCVVMxFzAVBgNVBAoTDlZlcmlTaWduLCBJbmMuMTcwNQYDVQQLEy5DbGFz\r"\
"cyAzIFB1YmxpYyBQcmltYXJ5IENlcnRpZmljYXRpb24gQXV0aG9yaXR5MB4XDTk2\r"\
"MDEyOTAwMDAwMFoXDTI4MDgwMTIzNTk1OVowXzELMAkGA1UEBhMCVVMxFzAVBgNV\r"\
"BAoTDlZlcmlTaWduLCBJbmMuMTcwNQYDVQQLEy5DbGFzcyAzIFB1YmxpYyBQcmlt\r"\
"YXJ5IENlcnRpZmljYXRpb24gQXV0aG9yaXR5MIGfMA0GCSqGSIb3DQEBAQUAA4GN\r"\
"ADCBiQKBgQDJXFme8huKARS0EN8EQNvjV69qRUCPhAwL0TPZ2RHP7gJYHyX3KqhE\r"\
"BarsAx94f56TuZoAqiN91qyFomNFx3InzPRMxnVx0jnvT0Lwdd8KkMaOIG+YD/is\r"\
"I19wKTakyYbnsZogy1Olhec9vn2a/iRFM9x2Fe0PonFkTGUugWhFpwIDAQABMA0G\r"\
"CSqGSIb3DQEBAgUAA4GBALtMEivPLCYATxQT3ab7/AoRhIzzKBxnki98tsX63/Do\r"\
"lbwdj2wsqFHMc9ikwFPwTtYmwHYBV4GSXiHx0bH/59AhWM1pF+NEHJwZRDmJXNyc\r"\
"AA9WjQKZ7aKQRUzkuxCkPfAyAw7xzvjoyVGM5mKf5p/AfbdynMk2OmufTqj/ZA1k\r"\
"-----END CERTIFICATE-----”;
WIFI_PRO.setCA(TRUSTED_CA);
}
Note: Firmware versions ID811d15 and greater use SSL3/TLS1.2 protocol only.
The
setTCPclient() function opens a Transmission Control Protocol (TCP) client socket and attempts to connect to the specified port on a server defined as input. Therefore, this function needs three different inputs:- Host: The server name may be any legal Internet server name that can be resolved by module's DNS (Domain Name Server) settings. The server name can also be specified as an absolute IP address given in dot-decimal notation.
- Remote port: It is assumed that the server system is listening on the specified port.
- Local port: This is the local port when opening the TCP socket.
Upon successfully opening and connecting the TCP socket to the <Host>:<Remote port>, a socket handle is returned. The socket handle is stored in the
_socket_handle attribute. This handle is in the range 0 to 9. This handle is needed to reference the socket in all following socket commands.Example of use:
{
char HOST[] = "192.168.5.152";
char REMOTE_PORT[] = "2000";
char LOCAL_PORT[] = "3000";
WIFI_PRO.setTCPclient( HOST, REMOTE_PORT, LOCAL_PORT);
}
Related variable:
WIFI_PRO._socket_handle → Stores the TCP socket handleExample of use for TCP sockets:
Figure: TCP client in Waspmote vs TCP server in laptop
The
setTCPserver() function opens a TCP listening socket on the local IP address and the specified port. The second input parameter specifies the maximum number of remote concurrent connections allowed through the listening socket. Thus, this function needs 2 different inputs:- Local port: The listening port to be used by a remote system when connecting to the WiFi PRO module.
- Max number of clients: Specifies the maximum number of active connections that may be concurrently established through the listening socket.
Once the listening socket is open, it automatically accepts remote connect requests up to the maximum allowed. When a remote system connects through the listening socket, a new TCP socket is spawned internally ready to send and receive data.
The
getAllSocketStatus() function allows the user to update the information of all active sockets connected through a listening socket. The information for each one of the active sockets is stored in a structure called listen_socket_t. There are ten structures defined in the Waspmote libraries for permitting up to ten connections simultaneously.The definition of the array of sockets structures is:
listen_socket_t socket[10];
The definition of the structure is:
struct listen_socket_t
{
uint16_t handle; // socket handle
int8_t status; // 0: active; -1: non-active
char ip[16]; // xxx.xxx.xxx.xxx
uint16_t port; // remote connection port
int size; // size of pending bytes
};
Example of use for TCP server:
The
setUDP() function opens a UDP (User Datagram Protocol) socket and sets the remote system’s <Host>:<port> address. Therefore, this function needs three different inputs:- Host: Logical name of the target server or a host IP address. The remote system’s name may be any legal Internet server name that can be resolved by module's DNS (Domain Name Server) settings. The server name may also be specified as an absolute IP address given in dot-decimal notation. When the <Host> is defined, the resulting UDP socket is created and connected. If <Host>=0.0.0.0, the socket is created but remains unconnected. The first UDP packet to arrive automatically latches the sender’s IP port, in effect connecting the socket. <Host> may be a subnet directed Broadcast address which allows to broadcast packets to the immediate subnet, not crossing gateways. For example, to broadcast to subnet 192.168.x.x on destination port 1234: Host=”192.168.255.255” and Remote port=“1234”. <Host> may be a multicast IP address in the range 224.0.0.0 to 239.255.255.255. IP multicast datagrams will not cross gateways. In this case, data is sent and received on <Remote port>. <Local port> is ignored.
- Remote port: Specifies the remote system’s port.
- Local port: Specifies the local port to use.
Upon successfully opening and connecting the UDP socket to <Host>:<Remote port>, a socket handle is returned. The socket handle is stored in the
_socket_handle attribute. The socket handle is in the range 0 to 9 and is used to reference the socket in all following socket commands.Note: The WiFi PRO will only be able to receive UDP packets from the specified <Host> IP address to the specified <Local port>. In the case other connections are needed it is possible to establish new UDP sockets with different hosts.
Example of use:
{
char HOST[] = "192.168.5.152";
char REMOTE_PORT[] = "2000";
char LOCAL_PORT[] = "3000";
WIFI_PRO.setUDP( HOST, REMOTE_PORT, LOCAL_PORT);
}
Related variable:
WIFI_PRO._socket_handle → Stores the UDP socket handleExamples of use for UDP sockets:
The
send() function sends a byte stream to the socket specified by the socket handle input. This function needs two different inputs:- Socket handle: A TCP/UDP socket handle of a previously open socket.
- Data: This is the stream of data to send to the TCP/UDP socket. This stream of data can be defined as a simple string message. Or an array of bytes, specifying a third input for the length of the array of bytes to send.
Example of use for the string message:
{
WIFI_PRO.send( WIFI_PRO._socket_handle, “this is a message”);
}