AS5311 linear encoder

Other Hardware Sensors
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A short demo code for AS5311 with SSI protocol and Arduino UNO.
Test performed with SSI protocol on the demo board AS5311-TS_EK_AB and 1mm pole length magnet strip provided with the kit.
I didn't find a good example online so here is mine.

I only find this library online: GitHub - muerzi/AS5311: Arduino Library for ams ag AS5311 12bit linear position sensor
There is 10ms delays in it which are not necessary because Read-out frequency is 1MHZ
I use shiftIn in the code rather than digitalRead

00:00 With magnet away mag is weak ~250, control code is 101 and position is random
00:05 With magnet on the AS5030 mag=1023 and pos=3135
00:08 Position overflow when pos over 4096

Sorry, the comment in the code are mainly in french.

//Only 6 wire to connectr
#define DO 2
#define CLK 3
#define CS 4
//GND: GND
//Prog: GND
//5V: 5V

void setup() {
  pinMode(DO, INPUT);
  pinMode(CLK, OUTPUT);
  pinMode(CS, OUTPUT);
  digitalWrite(CLK, 1);  //CLK
  digitalWrite(CS, 1);   //Csn
  Serial.begin(9600);
  delay(1000);
}

void loop() {
  //lecture pos shiftin
  digitalWrite(CLK, 1);                            //position-> CLK=1 avant CS=0
  digitalWrite(CS, 0);                             //debut lecture
  digitalWrite(CLK, 0);                            //passage à 0 pour lecture sur front montant
  unsigned int pos1 = shiftIn(DO, CLK, MSBFIRST);  // lecture un octet
  unsigned int pos2 = shiftIn(DO, CLK, MSBFIRST);  //lecture octet suivant
  digitalWrite(CS, 1);                             //fin de lecture
  unsigned int pos = (pos1 << 4) + (pos2 >> 4);    //assemblage des 2 octets:on garde les 12 premiers bits lus
  Serial.print("pos:" + (String)pos);
  Serial.print(",");

  //lecture mag shiftin
  digitalWrite(CLK, 0);  //magnitude->CLK=0 avant CS=0
  digitalWrite(CS, 0);   //debut lecture
  unsigned int mag1 = shiftIn(DO, CLK, MSBFIRST);
  unsigned int mag2 = shiftIn(DO, CLK, MSBFIRST);
  digitalWrite(CS, 1);                           //fin de lecture
  unsigned int mag = (mag1 << 4) + (mag2 >> 4);  //assemblage des 2 octets:on garde les 12 premiers bits lus
  Serial.print("mag:" + (String)mag);
  Serial.print(",");

  //Data validity verification
  //Must be 100 for valid data
  //OCF (Offset Compensation Finished), logic high indicates the finished Offset Compensation Algorithm. If this bit is not set, the data at D11:D0 (likewise M11:M0) may be invalid.
  //COF (Cordic Overflow), logic high indicates an out of range error in the CORDIC part. When this bit is set, the data at D11:D0 (likewise M11:M0) is invalid.
  //LIN (Linearity Alarm), logic high indicates that the input field generates a critical output linearity.
  //Note: La meme opération est possible sur pos pour extraire OCF+COF+LIN
  Serial.print("control:");
  Serial.print((mag2 >> 1) & (0b111), BIN);  //OCF+COF+LIN -- 100=OK
    //fin
  Serial.println();
  //delay(1000);
}

The code may be improved with SPI
No help needed here(my test is fully functional) but comments or improvements welcome!

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