Arduino で遊ぼう(3) XBeeとシリアル接続してAPIモード

Arduino とXBee wifiをシリアルで接続して、APIモードで動かしました。

XBee wifiにはtelnetで接続すると、

受信パケットをエコーバックします。

シリアルのボーレートは57600bpsまでしかうごきませんでした。

とりあえずのコード

(汚い…、。)

/*

 XBee WiFi Connected Serial.

 XBee works in API Mode.

 Receie Serial and Parse API packet,

 then echo back by API packet.

 */

/**

 * 送信パケットの生成

 */

int makeXBeeApiSendIp(byte* pPacket, unsigned short u16Size,

byte* pbIpAddrDst, byte* pbPortDst, byte* pbPayload, word length)

{

if(u16Size < length + 16)

{

Serial.println("buffer too short");

return -1;

}

// パケット生成

pPacket[0] = 0x7E;

// length

        u16Size = length + 12;

pPacket[1] = u16Size >> 8;

pPacket[2] = u16Size & 0x00FF;

// API Cmd

pPacket[3] = 0x20;

// FrameID

pPacket[4] = 0x00;

// IpAddrDst

pPacket[5] = pbIpAddrDst[0];

pPacket[6] = pbIpAddrDst[1];

pPacket[7] = pbIpAddrDst[2];

pPacket[8] = pbIpAddrDst[3];

// PortDst

pPacket[9] = pbPortDst[0];

pPacket[10] = pbPortDst[1];

// PortSrc

pPacket[11] = 0x26;

pPacket[12] = 0x16;

// Packet Type

pPacket[13] = 0x01; //< TCP, Connection Keep

//

pPacket[14] = 0x00;

// Payload

for(int i=0; i<length; i++)

{

pPacket[15 + i] = pbPayload[i];

}

// チェックサム計算

byte sum = 0;

for(int i=0; i<length + 12; i++)

{

sum += pPacket[3 + i];

}

pPacket[length + 15] = 0xFF - sum;

return length + 16;

}

/**

 * 受信パケットのダンプ

 */

void printPayload(byte* pPayload, word length)

{

  if(0 < length)

  {

    Serial.println("dump");

for(word i = 0; i<length; i++)

{

Serial.print(pPayload[i], HEX);

Serial.print(",");

}

        Serial.println();

  }

}

/**

 * 受信パケットのパース

 */

byte g_pbIpAddrSrc[4];

byte g_pbPortSrc[2];

byte* g_pbPayload;

int parseXBeeApiReceiveIp(byte* pPacket, unsigned short u16Size,

byte* pbIpAddrSrc, byte* pbPortSrc, byte** ppbPayload) {

// APIコード確認

if (0xB0 != pPacket[3]) {

// Serial.print("wrong api code:");

// Serial.println(pPacket[3]);

return -1;

}

// 送信元IPアドレス取得

pbIpAddrSrc[0] = pPacket[4];

pbIpAddrSrc[1] = pPacket[5];

pbIpAddrSrc[2] = pPacket[6];

pbIpAddrSrc[3] = pPacket[7];

//        Serial.write(pbIpAddrSrc, 4);

//        Serial.println();

// 送信元ポート取得

pbPortSrc[0] = pPacket[10];

pbPortSrc[1] = pPacket[11];

//        Serial.write(pbPortSrc, 2);

//        Serial.println();

// ペイロード取得

*ppbPayload = &pPacket[14];

//        Serial.println(pPacket[1]);

//        Serial.println(pPacket[2]);

return ((int) pPacket[1] << 8) + (int) pPacket[2] - 11;

}

/**

 * 受信処理

 */

#define RECEIVE_IP 1

unsigned char u8ReceiveMode = 0;

#define RECEIVE_MODE_IDLE 0

#define RECEIVE_MODE_LEN1 1

#define RECEIVE_MODE_LEN2 2

#define RECEIVE_MODE_DATA 3

#define RECEIVE_MODE_CS 4

#define APIPACKET_SIZE_MAX 1024

byte g_pu8ApiPacket[APIPACKET_SIZE_MAX];

unsigned short g_u16ApiPacketSize;

unsigned short g_u16ApiPacketLength;

int parseChar(byte data) {

// Serial.println(data, HEX);

switch (u8ReceiveMode) {

case RECEIVE_MODE_IDLE:

// wait for "0x7E"

if (0x7E == data) {

g_u16ApiPacketSize = 0;

g_u16ApiPacketLength = 0;

g_pu8ApiPacket[g_u16ApiPacketSize++] = data;

u8ReceiveMode = RECEIVE_MODE_LEN1;

// Serial.println("api start");

}

break;

case RECEIVE_MODE_LEN1:

g_pu8ApiPacket[g_u16ApiPacketSize++] = data;

u8ReceiveMode = RECEIVE_MODE_LEN2;

break;

case RECEIVE_MODE_LEN2:

g_pu8ApiPacket[g_u16ApiPacketSize++] = data;

u8ReceiveMode = RECEIVE_MODE_DATA;

g_u16ApiPacketLength = ((unsigned short) g_pu8ApiPacket[1] << 8)

+ (unsigned short) g_pu8ApiPacket[2];

// Serial.print("get len :");

// Serial.println(g_u16ApiPacketLength);

if (g_u16ApiPacketLength > (APIPACKET_SIZE_MAX - 4)) {

Serial.println("invalid data len");

u8ReceiveMode = RECEIVE_MODE_IDLE;

}

break;

case RECEIVE_MODE_DATA:

g_pu8ApiPacket[g_u16ApiPacketSize++] = data;

if ((g_u16ApiPacketSize - 3) >= g_u16ApiPacketLength) {

u8ReceiveMode = RECEIVE_MODE_CS;

// Serial.println("get data");

}

break;

case RECEIVE_MODE_CS:

g_pu8ApiPacket[g_u16ApiPacketSize++] = data;

u8ReceiveMode = RECEIVE_MODE_IDLE;

// Serial.println("get cs");

return RECEIVE_IP;

break;

default:

break;

}

return 0;

}

byte RXLED = 13;

byte toggle = 0;

void setup() {

pinMode(RXLED, OUTPUT);  // Set RX LED as an output

// TX LED is set as an output behind the scenes

Serial.begin(115200); //This pipes to the serial monitor

Serial1.begin(4800); //This is the UART, pipes to sensors attached to board

}

void loop() {

if (0 < Serial.available()) {

                byte data = Serial.read();

Serial1.write(g_pu8ApiPacket, makeXBeeApiSendIp(g_pu8ApiPacket, APIPACKET_SIZE_MAX, g_pbIpAddrSrc, g_pbPortSrc, &data, 1));

if (0 == toggle) {

digitalWrite(RXLED, LOW);   // set the LED on

TXLED0; //TX LED is not tied to a normally controlled pin

toggle = 1;

} else {

digitalWrite(RXLED, HIGH);    // set the LED off

TXLED1;

toggle = 0;

}

}

if (0 < Serial1.available()) {

// Serial.write(parseChar(Serial1.read()));

if (RECEIVE_IP == parseChar(Serial1.read())) {

int len = parseXBeeApiReceiveIp(g_pu8ApiPacket, g_u16ApiPacketSize,

g_pbIpAddrSrc, g_pbPortSrc, &g_pbPayload);

Serial.print("receive ip packet:");

Serial.println(len);

printPayload(g_pbPayload, len);

// echo

                        byte data = *g_pbPayload;

Serial1.write(g_pu8ApiPacket, makeXBeeApiSendIp(g_pu8ApiPacket, APIPACKET_SIZE_MAX, g_pbIpAddrSrc, g_pbPortSrc, &data, 1));

}

}

}