Hello,
I am working on a system to read multiple TPM-Sensors (Tire Pressure Monitoring) with an Arduino. These Sensors send their data ota with 433 MHz (Europe). I bought an 433 MHz Transceiver ER400TRS to get receive those data.
I wrote the following small sketch to test the communication between the Receiver and my Arduino:
/*
* ARDUINO TPMS READING SKETCH
* DATE: 08/JUL/2015
* AUTHOR: DANIEL SEE
* PIN SETUP:
* ER400TRS ----> SIGNAL ----> ARDUINO
* PIN_1 ----> ANTENNA
* PIN_2 ----> RF GND
* PIN_3 ----> RSSI ----> A0
* PIN_4 ----> BUSY OUTPUT ----> D2
* PIN_5 ----> SDO ----> D10
* PIN_6 ----> SDI ----> D11
* PIN_7 ----> Host Ready ----> GND
* PIN_8 ----> Vcc ----> 5V
* PIN_9 ----> GND ----> GND
*
*/
#include <SoftwareSerial.h>
#define rx 10
#define tx 11
#define rssi A0
#define busy 2
char* question = "ER_CMD#U?";
SoftwareSerial S2 = SoftwareSerial(rx, tx);
String serial_read = "";
void setup() {
pinMode(rx, INPUT);
pinMode(tx, OUTPUT);
pinMode(rssi, INPUT);
pinMode(2, INPUT);
Serial.begin(19200);
S2.begin(19200);
Serial.println("\n[ER400TRS TEST]");
Serial.println(question);
S2.print(question);
}
void loop() {
if (S2.available()>0) {
Serial.println("[X]" + (char)S2.read());
}
}
void serialEvent() {
while (Serial.available()) {
char received = (char)Serial.read();
serial_read += received;
delay(5);
}
Serial.println("Received: " + serial_read);
S2.print(serial_read);
serial_read = "";
}
ER_CMD#U? questions the baud-rate from the Receiver 8it should be 19200 default.
I only receive:
[X]
[ER400TRS TEST]
ER_CMD#U?
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
[X]
And every time the RDKS sends data I get more of those empty data chunks ("[X]") I expected sth. like "[X]ABCADA" or so....
Can any1 please help me, I dont know whats wrong 
Here the Datasheet of the Receiver:
ER400TRS