If using espconn in ESP8266_RTOS_SDK, please call espconn_init in user_init as initialization.
Sample code below is based on ESP8266_NONOS_SDK.
We suggest to call the next espconn_send in espconn_sent_callback which means that the previous packet is sent.
Or users could enable the espconn_write_finish_callback which means the data sending by espconn_send was written into the write-buffer or already sent, and call the next espconn_send in espconn_write_finish_callback.
The write-buffer can store 8 packets at most, waiting for the TCP ACK. The size of write-buffer is 2920 bytes.
Introduce an API here：
Code: Select all
Function: Set option of TCP connection
Prototype:
sint8 espconn_set_opt(
struct espconn *espconn,
uint8 opt
)
Parameter:
struct espconn *espconn : corresponding connected control structure
uint8 opt : Option of TCP connection
bit 0: 1: free memory after TCP disconnection happen need not wait 2 minutes;
bit 1: 1: disable nalgo algorithm during TCP data transmission, quiken the data transmission.
bit 2: 1: enable espconn_write_finish_callback.
bit 3: 1: enable TCP keep-alive function
Return:
0 : succeed
Non-0 : error (please refer to espconn.h for details.)
e.g. ESPCONN_ARG: illegal argument，can’t find TCP connection according to structure espconn
Note:
In general, we need not call this API;
If call espconn_set_opt, please call it in TCP connected callback.
Sample code of send TCP data continually is as bellow
1. call espconn_set_opt to enable write buffer;
2. register a write finish callback;
3. send next packet in write finish callback.
Code: Select all
LOCAL os_timer_t test_timer;
LOCAL struct espconn user_tcp_conn;
LOCAL struct _esp_tcp user_tcp;
ip_addr_t tcp_server_ip;
/******************************************************************************
* FunctionName : user_tcp_recv_cb
* Description : receive callback.
* Parameters : arg -- Additional argument to pass to the callback function
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
user_tcp_recv_cb(void *arg, char *pusrdata, unsigned short length)
{
//received some data from tcp connection
os_printf("tcp recv !!! %s \r\n", pusrdata);
}
/******************************************************************************
* FunctionName : user_tcp_sent_cb
* Description : data sent callback.
* Parameters : arg -- Additional argument to pass to the callback function
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
user_tcp_sent_cb(void *arg)
{
//data sent successfully
}
/******************************************************************************
* FunctionName : user_tcp_discon_cb
* Description : disconnect callback.
* Parameters : arg -- Additional argument to pass to the callback function
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
user_tcp_discon_cb(void *arg)
{
//tcp disconnect successfully
os_printf("tcp disconnect succeed !!! \r\n");
}
/******************************************************************************
* FunctionName : user_tcp_write_finish
* Description : Data need to be sent by espconn_sent has been written into write buffer successfully,
call espconn_sent to send next packet is allowed.
* Parameters : pespconn -- the espconn used to connetion with the host
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
user_tcp_write_finish(void *arg)
{
struct espconn *pespconn = arg;
espconn_sent(pespconn, "Hello World!", 12);
}
/******************************************************************************
* FunctionName : user_sent_data
* Description : Processing the application data and sending it to the host
* Parameters : pespconn -- the espconn used to connetion with the host
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
user_sent_data(struct espconn *pespconn)
{
espconn_sent(pespconn, "Hello World!", 12);
}
/******************************************************************************
* FunctionName : user_tcp_connect_cb
* Description : A new incoming tcp connection has been connected.
* Parameters : arg -- Additional argument to pass to the callback function
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
user_tcp_connect_cb(void *arg)
{
struct espconn *pespconn = arg;
os_printf("connect succeed !!! \r\n");
espconn_regist_recvcb(pespconn, user_tcp_recv_cb);
espconn_regist_sentcb(pespconn, user_tcp_sent_cb);
espconn_regist_disconcb(pespconn, user_tcp_discon_cb);
espconn_set_opt(pespconn, 0x04); // enable write buffer
espconn_regist_write_finish(pespconn, user_tcp_write_finish); // register write finish callback
user_sent_data(pespconn);
}
/******************************************************************************
* FunctionName : user_tcp_recon_cb
* Description : reconnect callback, error occured in TCP connection.
* Parameters : arg -- Additional argument to pass to the callback function
* Returns : none
*******************************************************************************/
LOCAL void ICACHE_FLASH_ATTR
user_tcp_recon_cb(void *arg, sint8 err)
{
//error occured , tcp connection broke. user can try to reconnect here.
os_printf("reconnect callback, error code %d !!! \r\n",err);
}
/******************************************************************************
* FunctionName : user_check_ip
* Description : check whether get ip addr or not
* Parameters : none
* Returns : none
*******************************************************************************/
void ICACHE_FLASH_ATTR
user_check_ip(void)
{
struct ip_info ipconfig;
//disarm timer first
os_timer_disarm(&test_timer);
//get ip info of ESP8266 station
wifi_get_ip_info(STATION_IF, &ipconfig);
if (wifi_station_get_connect_status() == STATION_GOT_IP && ipconfig.ip.addr != 0)
{
os_printf("got ip !!! \r\n");
// Connect to tcp server as NET_DOMAIN
user_tcp_conn.proto.tcp = &user_tcp;
user_tcp_conn.type = ESPCONN_TCP;
user_tcp_conn.state = ESPCONN_NONE;
const char esp_server_ip[4] = {X, X, X, X}; // remote IP of tcp server
os_memcpy(user_tcp_conn.proto.tcp->remote_ip, esp_server_ip, 4); // remote ip of tcp server
user_tcp_conn.proto.tcp->remote_port = TCP_SERVER_PORT; // remote port of tcp server
user_tcp_conn.proto.tcp->local_port = espconn_port(); //local port of ESP8266
espconn_regist_connectcb(&user_tcp_conn, user_tcp_connect_cb); // register connect callback
espconn_regist_reconcb(&user_tcp_conn, user_tcp_recon_cb); // register reconnect callback as error handler
espconn_connect(&user_tcp_conn); // tcp connect
}
else
{
if ((wifi_station_get_connect_status() == STATION_WRONG_PASSWORD ||
wifi_station_get_connect_status() == STATION_NO_AP_FOUND ||
wifi_station_get_connect_status() == STATION_CONNECT_FAIL))
{
os_printf("connect fail !!! \r\n");
}
else
{
//re-arm timer to check ip
os_timer_setfn(&test_timer, (os_timer_func_t *)user_check_ip, NULL);
os_timer_arm(&test_timer, 100, 0);
}
}
}
/******************************************************************************
* FunctionName : user_set_station_config
* Description : set the router info which ESP8266 station will connect to
* Parameters : none
* Returns : none
*******************************************************************************/
void ICACHE_FLASH_ATTR
user_set_station_config(void)
{
// Wifi configuration
char ssid[32] = "SSID";
char password[64] = "PASSWORD";
struct station_config stationConf;
//need not mac address
stationConf.bssid_set = 0;
//Set ap settings
os_memcpy(&stationConf.ssid, ssid, 32);
os_memcpy(&stationConf.password, password, 64);
wifi_station_set_config(&stationConf);
//set a timer to check whether got ip from router succeed or not.
os_timer_disarm(&test_timer);
os_timer_setfn(&test_timer, (os_timer_func_t *)user_check_ip, NULL);
os_timer_arm(&test_timer, 100, 0);
}
/******************************************************************************
* FunctionName : user_init
* Description : entry of user application, init user function here
* Parameters : none
* Returns : none
*******************************************************************************/
void user_init(void)
{
os_printf("SDK version:%s\n", system_get_sdk_version());
//Set softAP + station mode
wifi_set_opmode(STATIONAP_MODE);
//ESP8266 connect to router
user_set_station_config();
}