I am pairing an Arduino UNO with a Yost Labs 3-Space Sensor Nano, the user manual for said sensor can be found here.
This is my code, pretty straight forward (although this is my first time working with SPI). I am 100% sure the wiring is correct.
I believe that as per the user manual, this should successfully return 3 floats in 4 bytes each, corresponding to the filtered euler angles of pitch, yaw, and roll. However, all I am reading is bytes full of 0xFF which I believe corresponds to null / no command.
Are there any visible errors in my code?
#include <SPI.h>
SPISettings settings(6000000, MSBFIRST, SPI_MODE0 ); //variable to hold SPI settings
//Set Slave Select, MOSI, MISO, CLK
const int CSN = 10;
const int SO = 11;
const int SI = 12;
const int CLK = 13;
// Needed to convert the bytes from SPI to float
union u_types {
byte b[4];
float fval;
} data[3]; // Create 3 unions, one for each euler angle
void setup() {
//Set Pin Modes
pinMode(CSN, OUTPUT);
pinMode(SI, OUTPUT);
pinMode(SO, INPUT);
pinMode(CLK, OUTPUT);
//Set Slave Select High to Start i.e disable chip
digitalWrite(CSN, HIGH);
//Initialize SPI
SPI.begin();
//pour a bowl of serial
Serial.begin(9600);
}
//function to transfer commands through SPI
byte transferByte(byte byteToWrite) {
byte Result = 0x00;
digitalWrite(CSN,LOW);
delay(1);
Result = SPI.transfer(byteToWrite);
delay(1);
digitalWrite(CSN,HIGH);
return Result;
}
//function to swap endian
void endianSwap(byte temp[4]) {
byte myTemp = temp[0];
temp[0] = temp[3];
temp[3] = myTemp;
myTemp = temp[1];
temp[1] = temp[2];
temp[2] = myTemp;
}
void loop() {
SPI.beginTransaction(settings);
// Clear the internal data buffer on the IMU
byte result = transferByte(0x01);
Serial.print("Cleared internal buffer. Result: "),Serial.println(result);
// Send start of packet:
result = transferByte(0xF6);
Serial.print("Send start of packet. Result: "),Serial.println(result);
// Send command (tared euler angles)
result = transferByte(0x01);
Serial.print("Send commmand 0x01. Result: "),Serial.println(result);
// Get status of device:
result = transferByte(0xFF);
Serial.print("Status of device. Result: "),Serial.println(result);
while (result != 0x01) { // Repeat until device is Ready
delay(1);
result = transferByte(0xFF);
Serial.print("Status of device. Result: "),Serial.println(result);
}
// Get the 12 bytes of return data from the device:
for (int ii=0; ii<3; ii++) {
for (int jj=0; jj<4; jj++) {
data[ii].b[jj] = transferByte(0xFF);
delay(1);
}
}
SPI.endTransaction();
for( int mm=0; mm<3; mm++) {
endianSwap(data[mm].b);
}
Serial.print("fval 1:"), Serial.println(data[0].fval);
Serial.print("fval 2:"), Serial.println(data[1].fval);
Serial.print("fval 3:"), Serial.println(data[2].fval);
delay(3000);
}
