arduinoReadF — Read data from an arduino port using the Csound-Arduino protocol.


Plugin opcode in serial.

Read integer data from an arduino port with CsoundArduino protocol.


kval arduinoReadF iPort, iStream1,
      iStream2, iStream3


iPort -- port number obtained from a arduinoStart opcode.

iStream1, iStream2, iStream3 -- Numbers of the three data streams in the range 0 to 30. Each stream carries 10 bits of the 30 bits floating point result. The division is created in the Arduino sketch encapsulated in the put_float function.

kval -- floating point value read.

[Note] Note
The value transmitted is two bits shorter in the mantissa than produced on the Arduino so there is a little error introduced.


Here is an example of the arduinoReadF opcode. It uses the file arduinoReadF.csd.

Example 59. Example of the arduinoReadF opcode.

See the sections Real-time Audio and Command Line Flags for more information on using command line flags.

Arduino-Joystick2Csound1g-fm1-port (version with smoothing)

- Push Joystick button to turn on note
- Use JoystickX to offset and control the modulation index of
  the foscil opcode from 0-40 via the scale opcode
- Use JoystickY to offset and control the Frequency of the foscil
  opcode up/down two octaves via the scale opcode



sr = 44100
ksmps = 441
nchnls = 2
0dbfs = 1

giport init 0

// NOTE: change USB port "/dev/cu.usbmodem1414301" to correspond
//       with USB port used by Arduino on your system
giport arduinoStart  "//dev/ttyACM0", 9600    // for GNULinux

instr 1

kk  arduinoReadF  giport, 1, 2, 3
printks "kk=%f\n", 0.5, kk



f 1 0 16384 10 1

i 1 0 1




// Float Example

// John ffitch & Richard Boulanger
// December 7, 2020

// BreadBoard & Arduino Setup

void setup() {
              // NOTE: Digital pins can be either inputs or outputs.


// put_val( ) - a function to send data values to the Csound
//              "arduinoRead" opcode
// The first argument of the put_val function "int senChan" sets
// the software channel number that Csound reads
// NOTE: "senChan" does "not" define the input pin that is used on
// the Arduino for a specific sensor
// The specific Arduino input pin used by any sensor is assigned
// and set elsewhere in the Arduino sketch and mapped to a
// user-defined put_val "senChan" channel

void put_val(int senChan, int senVal)
        // Set the Csound receive channel "senChan", and read from
        // the sensor data stream "senVal"
{       // The packing of the data is sssssvvv 0vvvvvvv where s is a
        // senChan bit, v a senVal bit and 0 is zero` bit
  int low = senVal&0x7f;
  int hi = ((senVal>>7)&0x0f) | ((senChan&0x0f)<<4);
  Serial.write(low); Serial.write(hi);

void put_float(int senChan1, int senChan2, int senChan3, float senVal)
  typedef union {
    float f;
    long i;
  } JOINT;
  JOINT x;
  x.f = senVal;
  put_val(senChan1, (x.i>> 2)& 0x3ff);
  put_val(senChan2, (x.i>>12)& 0x3ff);
  put_val(senChan3, (x.i>>22)& 0x3ff);

void loop() {

   Serial.write(0xf8);   // Synchronization Byte - (essential!) marks beginning of new serial frame





See Also

arduinoStart, arduinoStop, arduinoRead,


Author: John ffitch
Author: Richard Boulanger

New in version 6.15