Hi3861 WiFi操作,热点连接
之前我们使用Hi3861的时候,是使用AT指令连接到WiFi热点的。例如:
但是很多时候,我们需要实现开机后自动连接到某个热点,光靠AT指令不行。
Hi3861 为我们提供了WiFi操作的相关API,方便我们编写代码,实现热点连接。
1.代码实现
先直接上代码和操作演示。
跟我们最早的hello world代码一样,在app下新增业务wifi_demo,其中hello_world.c为业务代码,BUILD.gn为编译脚本,具体规划目录结构如下:
.
└── applications
└── sample
└── wifi-iot
└── app
│── wifi_demo
│ │── wifi_demo.c
│ └── BUILD.gn
└── BUILD.gn
Wifi_demo.c 代码如下:
- #include <stdio.h>
- #include <unistd.h>
- #include "ohos_init.h"
- #include "cmsis_os2.h"
- #include <unistd.h>
- #include "hi_wifi_api.h"
- //#include "wifi_sta.h"
- #include "lwip/ip_addr.h"
- #include "lwip/netifapi.h"
- #define APP_INIT_VAP_NUM 2
- #define APP_INIT_USR_NUM 2
- static struct netif *g_lwip_netif = NULL;
- /* clear netif's ip, gateway and netmask */
- void hi_sta_reset_addr(struct netif *pst_lwip_netif)
- {
- ip4_addr_t st_gw;
- ip4_addr_t st_ipaddr;
- ip4_addr_t st_netmask;
- printf("%s %d rn", __FILE__, __LINE__);
- if (pst_lwip_netif == NULL) {
- printf("hisi_reset_addr::Null param of netdevrn");
- return;
- }
- IP4_ADDR(&st_gw, 0, 0, 0, 0);
- IP4_ADDR(&st_ipaddr, 0, 0, 0, 0);
- IP4_ADDR(&st_netmask, 0, 0, 0, 0);
- netifapi_netif_set_addr(pst_lwip_netif, &st_ipaddr, &st_netmask, &st_gw);
- }
- void wifi_wpa_event_cb(const hi_wifi_event *hisi_event)
- {
- if (hisi_event == NULL)
- return;
- switch (hisi_event->event) {
- case HI_WIFI_EVT_SCAN_DONE:
- printf("WiFi: Scan results availablen");
- break;
- case HI_WIFI_EVT_CONNECTED:
- printf("WiFi: Connectedn");
- netifapi_dhcp_start(g_lwip_netif);
- break;
- case HI_WIFI_EVT_DISCONNECTED:
- printf("WiFi: Disconnectedn");
- netifapi_dhcp_stop(g_lwip_netif);
- hi_sta_reset_addr(g_lwip_netif);
- break;
- case HI_WIFI_EVT_WPS_TIMEOUT:
- printf("WiFi: wps is timeoutn");
- break;
- default:
- break;
- }
- }
- int hi_wifi_start_connect(void)
- {
- int ret;
- errno_t rc;
- hi_wifi_assoc_request assoc_req = {0};
- /* copy SSID to assoc_req */
- //热点名称
- rc = memcpy_s(assoc_req.ssid, HI_WIFI_MAX_SSID_LEN + 1, "15919500", 8); /* 9:ssid length */
- if (rc != EOK) {
- printf("%s %d rn", __FILE__, __LINE__);
- return -1;
- }
- /*
- * OPEN mode
- * for WPA2-PSK mode:
- * set assoc_req.auth as HI_WIFI_SECURITY_WPA2PSK,
- * then memcpy(assoc_req.key, "12345678", 8).
- */
- //热点加密方式
- assoc_req.auth = HI_WIFI_SECURITY_WPA2PSK;
- /* 热点密码 */
- memcpy(assoc_req.key, "11206582488", 11);
- ret = hi_wifi_sta_connect(&assoc_req);
- if (ret != HISI_OK) {
- printf("%s %d rn", __FILE__, __LINE__);
- return -1;
- }
- printf("%s %d rn", __FILE__, __LINE__);
- return 0;
- }
- int hi_wifi_start_sta(void)
- {
- int ret;
- char ifname[WIFI_IFNAME_MAX_SIZE + 1] = {0};
- int len = sizeof(ifname);
- const unsigned char wifi_vap_res_num = APP_INIT_VAP_NUM;
- const unsigned char wifi_user_res_num = APP_INIT_USR_NUM;
- unsigned int num = WIFI_SCAN_AP_LIMIT;
- printf("%s %d rn", __FILE__, __LINE__);
- ret = hi_wifi_init(wifi_vap_res_num, wifi_user_res_num);
- if (ret != HISI_OK) {
- printf("%s %d rn", __FILE__, __LINE__);
- //return -1;
- }
- printf("%s %d rn", __FILE__, __LINE__);
- ret = hi_wifi_sta_start(ifname, &len);
- if (ret != HISI_OK) {
- printf("%s %d rn", __FILE__, __LINE__);
- return -1;
- }
- /* register call back function to receive wifi event, etc scan results event,
- * connected event, disconnected event.
- */
- ret = hi_wifi_register_event_callback(wifi_wpa_event_cb);
- if (ret != HISI_OK) {
- printf("register wifi event callback failedn");
- }
- /* acquire netif for IP operation */
- g_lwip_netif = netifapi_netif_find(ifname);
- if (g_lwip_netif == NULL) {
- printf("%s: get netif failedn", __FUNCTION__);
- return -1;
- }
- /* start scan, scan results event will be received soon */
- ret = hi_wifi_sta_scan();
- if (ret != HISI_OK) {
- printf("%s %d rn", __FILE__, __LINE__);
- return -1;
- }
- sleep(5); /* sleep 5s, waiting for scan result. */
- hi_wifi_ap_info *pst_results = malloc(sizeof(hi_wifi_ap_info) * WIFI_SCAN_AP_LIMIT);
- if (pst_results == NULL) {
- printf("%s %d rn", __FILE__, __LINE__);
- return -1;
- }
- ret = hi_wifi_sta_scan_results(pst_results, &num);
- if (ret != HISI_OK) {
- printf("%s %d rn", __FILE__, __LINE__);
- free(pst_results);
- return -1;
- }
- for (unsigned int loop = 0; (loop < num) && (loop < WIFI_SCAN_AP_LIMIT); loop++) {
- printf("SSID: %sn", pst_results[loop].ssid);
- }
- free(pst_results);
- /* if received scan results, select one SSID to connect */
- ret = hi_wifi_start_connect();
- if (ret != 0) {
- printf("%s %d rn", __FILE__, __LINE__);
- return -1;
- }
- return 0;
- }
- void hi_wifi_stop_sta(void)
- {
- int ret;
- ret = hi_wifi_sta_stop();
- if (ret != HISI_OK) {
- printf("failed to stop stan");
- }
- ret = hi_wifi_deinit();
- if (ret != HISI_OK) {
- printf("failed to deinit wifin");
- }
- g_lwip_netif = NULL;
-
- }
- void WiFiExampleEntry(void)
- {
- hi_wifi_start_sta();
- }
- SYS_RUN(WiFiExampleEntry);
复制代码
Wifi_demo
目录下的BUILD.gn文件内容如下:
static_library("wifi_demo") {
sources = [
"wifi_demo.c"
]
include_dirs = [
"//utils/native/lite/include",
"//kernel/liteos_m/components/cmsis/2.0",
"//base/iot_hardware/interfaces/kits/wifiiot_lite",
"//vendor/hisi/hi3861/hi3861/third_party/lwip_sack/include",
"//foundation/communication/interfaces/kits/wifi_lite/wifiservice",
]
}
app
目录下的BUILD.gn文件内容修改如下:
import("//build/lite/config/component/lite_component.gni")
lite_component("app") {
features = [
"wifi_demo:wifi_demo",
]
}
编译烧录,查看串口数据:
可以看到有打印扫描到的热点名称:
SSID: 15919500
SSID: Netcore_FD55A7
同时最后打印:WiFi: Connected 成功连接上热点。
2.wifi api接口说明
Hi3861 提供了非常多的wifi相关API,主要文件是 hi_wifi_api.h
我们这里只列举最重要的几个API
(1)开启STA
int hi_wifi_sta_start(char *ifname, int *len);
(2)停止STA
int hi_wifi_sta_stop(void);
int hi_wifi_sta_scan(void);
(4)连接热点
int hi_wifi_sta_connect(hi_wifi_assoc_request *req);
其中hi_wifi_assoc_request *req 结构的定义如下:
这里需要注意的是,通常加密方式是:HI_WIFI_SECURITY_WPA2PSK
例如我家的热点的连接方式的代码实现如下:
- /* copy SSID to assoc_req */
- //热点名称
- rc = memcpy_s(assoc_req.ssid, HI_WIFI_MAX_SSID_LEN + 1, "15919500", 8); /* 9:ssid length */
- if (rc != EOK) {
- printf("%s %d rn", __FILE__, __LINE__);
- return -1;
- }
- /*
- * OPEN mode
- * for WPA2-PSK mode:
- * set assoc_req.auth as HI_WIFI_SECURITY_WPA2PSK,
- * then memcpy(assoc_req.key, "12345678", 8).
- */
- //热点加密方式
- assoc_req.auth = HI_WIFI_SECURITY_WPA2PSK;
- /* 热点密码 */
- memcpy(assoc_req.key, "11206582488", 11);
复制代码