B4R Code Snippet 12 bit analog output for ESP32 with MCP492X via SPI

Built in DAC of ESP32 has 8 bit resolution.
My way to use: https://www.b4x.com/android/forum/t...tage-output-does-not-work.126928/#post-795752

If 12 bit resolution is needed MCP492X and SPI connection comes into play. Pin assignment using Arduino libs for ESP32 is kinda intransparent.
So here is my solution:

B4X:
#Region Project Attributes
    #AutoFlushLogs: True
    #CheckArrayBounds: True
    #StackBufferSize: 600
#End Region
'Ctrl+Click to open the C code folder: ide://run?File=%WINDIR%\System32\explorer.exe&Args=%PROJECT%\Objects\Src

Sub Process_Globals
    Public Serial1 As Serial
    Private astream As AsyncStreams
    Public n1, n2, n3 As Int  ' reserved for inline C parameters
End Sub

Private Sub AppStart
    Serial1.Initialize(115200) ' (256000)
    Log("AppStart")
    astream.Initialize(Serial1.Stream, "Astream_NewData", "Astream_Error")
   
    RunNative("iCsetup", Null)
   
    Do While True
        plot(2500,50)
        plot(1200,1200)
        plot(50,2500)
    Loop       
  
End Sub

Sub plot(x As Int,y As Int) As Int
    n1=x
    n2=y
    RunNative("iCplot", Null)
    Return n3
End Sub

Sub Astream_NewData (Buffer() As Byte)
    Log("Received: ", Buffer)
End Sub

Sub AStream_Error
    Log("error")
End Sub

#if C
/* https://github.com/michd/Arduino-MCP492X/blob/master/README.md
   https://lastminuteengineers.com/esp32-arduino-ide-tutorial/
   https://docs.espressif.com/projects/esp-idf/en/latest/esp32/api-reference/peripherals/spi_master.html

*          SPI2  SPI3 (used)
* Pin Name GPIO  Number
* CS0*      15     5+
* SCLK      14    18+
* MISO      12    19
* MOSI      13    23+
* QUADWP     2    22
* QUADHD     4    21
* 
*/

#include <MCP492X.h> // Include the library

#define PIN_SPI_CHIP_SELECT_DAC 5 // Or any pin you'd like to use

MCP492X myDac(PIN_SPI_CHIP_SELECT_DAC);

void iCsetup(B4R::Object* o) {
  // put your setup code here, To run once:
  myDac.begin();
}

void iCplot(B4R::Object* o) {
  // put your main code here, To be called repeatedly:

  // Write any value from 0-4095
  myDac.analogWrite( b4r_main::_n1);

  // If using an MCP4922, write a value To DAC B
  myDac.analogWrite(1,  b4r_main::_n2);
 
  b4r_main::_n3=0; // return code from inline function 
}

#End if
 
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