gs fan
Sample MQTT program - simple send and receive (MQ Telemetry Transport) for GainSpan Wi-Fi module
Dependencies: C12832 GSwifiInterface MQTT mbed-rtos mbed
mbedのMQTTグループで保守されているMQTTライブラリを GainSpan Wi-Fi モジュールへ対応させたサンプルです。
MQTT (MQ Telemetry Transport) とは、IoTやM2M向け デバイス間通信のためのプロトコルです。
MQTTサーバーには http://iot.eclipse.org/ のサンドボックスを使います。 送信したメッセージをエコーバックしてくるだけの動作をします。
mbed Application Board を使う場合は次の行のコメントアウトを外すとLCDへ表示するようになる。
#define MBED_APPLICATION_BOARD
GainSpanモジュールの接続ピンについては次の行で指定する。
gs = new GSwifiInterface(p9, p10, NC, NC, p30, NC, 9600); //tx, rx, cts, rts, reset, alarm, baud
Wi-Fiアクセスポイントは次の行で指定する。
#define SEC GSwifi::SEC_WPA_PSK #define SSID "SSID" #define PASS "PASSPHRASE"
Diff: Linux-example/LinuxIPStack.h
- Revision:
- 16:fd155e824a80
- Parent:
- 15:d8a31b66a85d
--- a/Linux-example/LinuxIPStack.h Fri Aug 01 23:46:08 2014 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,119 +0,0 @@
-#if !defined(LINUX_IPSTACK_H)
-#define LINUX_IPSTACK_H
-
-class IPStack
-{
-public:
- IPStack()
- {
-
- }
-
- int Socket_error(const char* aString)
- {
-
- if (errno != EINTR && errno != EAGAIN && errno != EINPROGRESS && errno != EWOULDBLOCK)
- {
- if (strcmp(aString, "shutdown") != 0 || (errno != ENOTCONN && errno != ECONNRESET))
- printf("Socket error %s in %s for socket %d\n", strerror(errno), aString, mysock);
- }
- return errno;
- }
-
- int connect(const char* hostname, int port)
- {
- int type = SOCK_STREAM;
- struct sockaddr_in address;
- int rc = -1;
- sa_family_t family = AF_INET;
- struct addrinfo *result = NULL;
- struct addrinfo hints = {0, AF_UNSPEC, SOCK_STREAM, IPPROTO_TCP, 0, NULL, NULL, NULL};
-
- if ((rc = getaddrinfo(hostname, NULL, &hints, &result)) == 0)
- {
- struct addrinfo* res = result;
-
- /* prefer ip4 addresses */
- while (res)
- {
- if (res->ai_family == AF_INET)
- {
- result = res;
- break;
- }
- res = res->ai_next;
- }
-
- if (result->ai_family == AF_INET)
- {
- address.sin_port = htons(port);
- address.sin_family = family = AF_INET;
- address.sin_addr = ((struct sockaddr_in*)(result->ai_addr))->sin_addr;
- }
- else
- rc = -1;
-
- freeaddrinfo(result);
- }
-
- if (rc == 0)
- {
- mysock = socket(family, type, 0);
- if (mysock != -1)
- {
- int opt = 1;
-
- //if (setsockopt(mysock, SOL_SOCKET, SO_NOSIGPIPE, (void*)&opt, sizeof(opt)) != 0)
- // printf("Could not set SO_NOSIGPIPE for socket %d", mysock);
-
- rc = ::connect(mysock, (struct sockaddr*)&address, sizeof(address));
- }
- }
-
- return rc;
- }
-
- int read(char* buffer, int len, int timeout_ms)
- {
- struct timeval interval = {timeout_ms / 1000, (timeout_ms % 1000) * 1000};
- if (interval.tv_sec < 0 || (interval.tv_sec == 0 && interval.tv_usec <= 0))
- {
- interval.tv_sec = 0;
- interval.tv_usec = 100;
- }
-
- setsockopt(mysock, SOL_SOCKET, SO_RCVTIMEO, (char *)&interval, sizeof(struct timeval));
-
- //printf("reading %d bytes\n", len);
- int rc = ::recv(mysock, buffer, (size_t)len, 0);
- if (rc == -1)
- Socket_error("read");
- //printf("read %d bytes\n", rc);
- return rc;
- }
-
- int write(char* buffer, int len, int timeout)
- {
- struct timeval tv;
-
- tv.tv_sec = 0; /* 30 Secs Timeout */
- tv.tv_usec = timeout * 1000; // Not init'ing this can cause strange errors
-
- setsockopt(mysock, SOL_SOCKET, SO_RCVTIMEO, (char *)&tv,sizeof(struct timeval));
- int rc = ::write(mysock, buffer, len);
- //printf("write rc %d\n", rc);
- return rc;
- }
-
- int disconnect()
- {
- return ::close(mysock);
- }
-
-private:
-
- int mysock;
-
-};
-
-#endif
\ No newline at end of file