57 lines
1.5 KiB
Markdown
57 lines
1.5 KiB
Markdown
# L04 Underwater Sonar
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[Datasheet](https://cdn-shop.adafruit.com/product-files/4664/4664_datasheet.pdf)
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## Cable Descriptions
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| Color | Name | Description | Remarks |
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|------------|------------|-------------------|---------|
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| red | VCC Power | input cable | 3.3V~5V |
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| black | GND Power | ground cable | // |
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| white | RX Trigger | input cable | (1) |
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| yellow | TX UART | output cable | (1) |
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## UART Data Frames
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| Frame data | Instruction | Byte |
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|--------------|---------------|--------|
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| Frame header | Fixed to 0xFF | 1 byte |
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| Data_H High | 8 bits of distance data | 1 byte
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| Data_L Low | 8 bits of distance data | 1 byte
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| SUM | Checksum of communication | 1 byte
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```c
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#include <SoftwareSerial.h>
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unsigned char buffer_RTT[4] = {0};
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uint8_t CS;
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#define COM 0x55
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SoftwareSerial mySerial(7, 8);
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void setup() {
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Serial.begin(115200);
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mySerial.begin(115200);
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}
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void loop() {
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mySerial.write(COM);
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delay(100);
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if(mySerial.available() > 0){
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delay(4);
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if(mySerial.read() == 0xff){
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buffer_RTT[0] = 0xff;
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for (int i=1; i<4; i++){
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buffer_RTT[i] = mySerial.read();
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}
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CS = buffer_RTT[0] + buffer_RTT[1]+ buffer_RTT[2];
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if(buffer_RTT[3] == CS) {
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int distance = (buffer_RTT[1] << 8) + buffer_RTT[2];
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Serial.print("Distance:");
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Serial.print(distance);
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Serial.println("mm");
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}
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}
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}
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}
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```
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