diff --git a/.arduino-ci.yml b/.arduino-ci.yml
index cecf585..9786d52 100644
--- a/.arduino-ci.yml
+++ b/.arduino-ci.yml
@@ -1,3 +1,18 @@
+platforms:
+  rpipico:
+    board: rp2040:rp2040:rpipico
+    package: rp2040:rp2040
+    gcc:
+      features:
+      defines:
+        - ARDUINO_ARCH_RP2040
+      warnings:
+      flags:
+
+packages:
+  rp2040:rp2040:
+    url: https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
+
 compile:
   # Choosing to run compilation tests on 2 different Arduino platforms
   platforms:
@@ -9,3 +24,4 @@ compile:
     - esp32
     # - esp8266
     # - mega2560
+    # - rpipico
diff --git a/MCP_DAC.cpp b/MCP_DAC.cpp
index a30b45b..17ccc8c 100644
--- a/MCP_DAC.cpp
+++ b/MCP_DAC.cpp
@@ -70,6 +70,19 @@ void MCP_DAC::begin(uint8_t select)
       mySPI->end();
       mySPI->begin(18, 19, 23, select);   // CLK=18 MISO=19 MOSI=23
     }
+  
+    #elif defined(ARDUINO_ARCH_RP2040)
+    
+    if (_useSPI1 == true) {
+      mySPI = &SPI1;
+    }else{
+      mySPI = &SPI;
+    }
+
+    mySPI->end();
+    mySPI->begin();
+
+
     #else              // generic hardware SPI
     mySPI = &SPI;
     mySPI->end();
@@ -85,8 +98,7 @@ void MCP_DAC::begin(uint8_t select)
   }
 }
 
-
-#if defined(ESP32)
+#if defined(ESP32) or defined(ARDUINO_ARCH_RP2040)
 void MCP_DAC::setGPIOpins(uint8_t clk, uint8_t miso, uint8_t mosi, uint8_t select)
 {
   _clock   = clk;
@@ -96,7 +108,20 @@ void MCP_DAC::setGPIOpins(uint8_t clk, uint8_t miso, uint8_t mosi, uint8_t selec
   digitalWrite(_select, HIGH);
 
   mySPI->end();  // disable SPI
+
+  #if defined(ESP32)
+
   mySPI->begin(clk, miso, mosi, select);
+
+  #elif defined(ARDUINO_ARCH_RP2040)
+
+  mySPI->setCS(select);
+  mySPI->setSCK(clk);
+  mySPI->setTX(mosi);
+
+  mySPI->begin();
+
+  #endif
 }
 #endif
 
diff --git a/MCP_DAC.h b/MCP_DAC.h
index c3f1b42..6f8bb90 100644
--- a/MCP_DAC.h
+++ b/MCP_DAC.h
@@ -13,7 +13,7 @@
 #include "SPI.h"
 
 
-#define MCP_DAC_LIB_VERSION       (F("0.1.6"))
+#define MCP_DAC_LIB_VERSION       (F("0.1.7"))
 
 
 
@@ -74,47 +74,77 @@ class MCP_DAC
   void     reset();
   bool     usesHWSPI() { return _hwSPI; };
 
-  // ESP32 specific
-  #if defined(ESP32)
+  
+  #if defined(ESP32)                    // ESP32 specific
+
   void     selectHSPI() { _useHSPI = true;  };
   void     selectVSPI() { _useHSPI = false; };
   bool     usesHSPI()   { return _useHSPI;  };
   bool     usesVSPI()   { return !_useHSPI; };
 
-  // to overrule ESP32 default hardware pins
+  // to overrule the ESP32s default hardware pins
+  void     setGPIOpins(uint8_t clk, uint8_t miso, uint8_t mosi, uint8_t select);
+
+  
+  #elif defined(ARDUINO_ARCH_RP2040)    // RP2040 specific
+
+  // check which SPI-Bus (SPI or SPI1) is used
+  void     selectSPI()  { _useSPI1 = false;  };
+  void     selectSPI1() { _useSPI1 = true; };
+  bool     usesSPI()    { return !_useSPI1;  };
+  bool     usesSPI1()   { return _useSPI1;  };
+
+  // to overrule the RP2040s default hardware pins
   void     setGPIOpins(uint8_t clk, uint8_t miso, uint8_t mosi, uint8_t select);
+
   #endif
 
+
 protected:
-  uint8_t  _dataOut;
-  uint8_t  _clock;
-  uint8_t  _select;
-  uint8_t  _latchPin = 255;
-  bool     _hwSPI;
-  uint32_t _SPIspeed = 16000000;
-
-  uint8_t  _channels;
-  uint16_t _maxValue;
-  uint16_t _value[2];
-  uint8_t  _gain;
-  bool     _buffered = false;
+  uint8_t  _dataOut;                // Data out Pin (MOSI)
+  uint8_t  _clock;                  // Clock Pin (SCK)
+  uint8_t  _select;                 // Chip Select Pin (CS)
+  uint8_t  _latchPin = 255;         // Latch-DAC Pin (LDAC)
+  bool     _hwSPI;                  // Hardware SPI (true) or Software SPI (false)
+  uint32_t _SPIspeed = 16000000;    // SPI-Bus Frequency
+
+  uint8_t  _channels;               // Number of DAC-Channels of a given Chip
+  uint16_t _maxValue;               // maximum value of a given Chip
+  uint16_t _value[2];               // Current value
+  uint8_t  _gain;                   // Programmable Gain Amplifier variable
+  bool     _buffered = false;       // Buffer for the Reference Voltage of the MCP49XX Series Chips
   bool     _active   = true;
 
   void     transfer(uint16_t data);
   uint8_t  swSPI_transfer(uint8_t d);
 
+  #if defined(ARDUINO_ARCH_RP2040)
+
+  SPIClassRP2040 * mySPI;
+
+  #else
+
   SPIClass    * mySPI;
+  
+  #endif
+  
   SPISettings _spi_settings;
 
   #if defined(ESP32)
+
   bool        _useHSPI = true;
+  
+  #elif defined(ARDUINO_ARCH_RP2040)
+
+  bool _useSPI1 = false;
+
   #endif
 };
 
 
 ///////////////////////////////////////////////////////////////
 //
-// 4800 Series
+// MCP4800 Series
 //
 class MCP4801 : public MCP_DAC
 {
@@ -160,7 +190,7 @@ class MCP4822 : public MCP_DAC
 
 ///////////////////////////////////////////////////////////////
 //
-// 4900 Series
+// MCP4900 Series
 //
 class MCP4901 : public MCP_DAC
 {
diff --git a/README.md b/README.md
index d921cbc..a5d5c1e 100644
--- a/README.md
+++ b/README.md
@@ -160,6 +160,48 @@ SPI0 and SPI1 are used to access flash memory. SPI2 and SPI3 are "user" SPI cont
 | not used |  MISO   = 12  |  MISO   = 19  |
 
 
+
+### RP2040 specific
+
+Select SPI bus on which the Device is on. Both need to be called before the **begin()** function. If the function is called after the **begin()** function, changes will only apply if the **end()** and then the **begin()** functions are called 
+
+- **void selectSPI()** Select the SPI bus (Standard, does not need to be called)
+- **void selectSPI1()** Select the SPI1 bus
+
+- **bool usesSPI()** returns true if SPI is used
+- **bool usesSPI1()** returns true if SPI1 is used
+
+#### experimental
+
+- **void setGPIOpins(uint8_t clk, uint8_t miso, uint8_t mosi, uint8_t select)** overrule GPIO pins of RP2040 for different SPI pins. needs to be called 
+AFTER the **begin()** function. Selcted pins must match the RP2040 pinout!
+
+
+```cpp
+void setup()
+{
+  MCP.selectSPI();    //use for SPI / SPI0
+  MCP.selectSPI1();   //use for SPI1
+  MCP.begin(17);
+  MCP.setGPIOpins(CLK, MISO, MOSI, SELECT);  // SELECT should match the param of begin()
+}
+```
+
+#### Pico connections to MCP4922 (example)
+
+The RP2040 has **two** SPI peripherals from which two can be used.
+
+SPI (SPI0) and SPI1 can both be usd to connect devices
+
+
+| MCP4922  |   SPI / SPI0  |      SPI1     |
+|:--------:|:-------------:|:-------------:|
+|  CS      |  SELECT = 17  |  SELECT = 13  | 
+|  SCK     |  SCLK   = 18  |  SCLK   = 14  | 
+|  SDI     |  MOSI   = 19  |  MOSI   = 15  | 
+| not used |  MISO   = 16  |  MISO   = 12  |
+
+
 ## Future
 
 - test test test and ....
diff --git a/examples/MCP4921_wave_generator_RP2040/.arduino-ci.yml b/examples/MCP4921_wave_generator_RP2040/.arduino-ci.yml
new file mode 100644
index 0000000..87acfe0
--- /dev/null
+++ b/examples/MCP4921_wave_generator_RP2040/.arduino-ci.yml
@@ -0,0 +1,27 @@
+platforms:
+  rpipico:
+    board: rp2040:rp2040:rpipico
+    package: rp2040:rp2040
+    gcc:
+      features:
+      defines:
+        - ARDUINO_ARCH_RP2040
+      warnings:
+      flags:
+
+packages:
+  rp2040:rp2040:
+    url: https://github.com/earlephilhower/arduino-pico/releases/download/global/package_rp2040_index.json
+
+compile:
+  # Choosing to run compilation tests on 2 different Arduino platforms
+  platforms:
+    # - uno
+    # - due
+    # - zero
+    # - leonardo
+    # - m4
+    # - esp32
+    # - esp8266
+    # - mega2560
+    - rpipico
diff --git a/examples/MCP4921_wave_generator_RP2040/MCP4921_wave_generator_RP2040.ino b/examples/MCP4921_wave_generator_RP2040/MCP4921_wave_generator_RP2040.ino
new file mode 100644
index 0000000..f677b91
--- /dev/null
+++ b/examples/MCP4921_wave_generator_RP2040/MCP4921_wave_generator_RP2040.ino
@@ -0,0 +1,198 @@
+//
+//    FILE: MCP4921_wave_generator_RP2040.ino
+//  AUTHOR: Rob Tillaart
+// PURPOSE: demo function generators
+//    DATE: 2021-02-03
+//     URL: https://github.com/RobTillaart/FunctionGenerator
+//
+//  depending on the platform, the range of "smooth" sinus is limited.
+//  other signals are less difficult so have a slightly larger range.
+//
+//  PLATFORM     SINUS    SQUARE  SAWTOOTH  TRIANGLE
+//  UNO          -100 Hz
+//  ESP32        -200 Hz  -1000   -250      -100
+//
+
+/*
+
+SPI Connections:
+
+MOSI:   GP 19
+SCK:    GP 18
+CS:     GP 17
+LDAC:   GP 2
+
+SPI1 Connections:
+
+MOSI:   GP 15
+SCK:    GP 14
+CS:     GP 13
+LDAC:   GP  3
+
+
+(Experimental) The Pins can be changed at any time via the setGPIO() command, view the Pico Pinout for compatible Pins
+
+*/
+
+
+
+#include "MCP_DAC.h"
+
+
+uint16_t     freq = 10;
+uint32_t   period = 0;
+uint32_t   halvePeriod = 0;
+
+
+// q = square
+// s = sinus
+// w = sawtooth
+// t = triangle
+// r = random
+char mode = 'q';
+
+
+MCP4921 MCP;
+uint16_t count;
+uint32_t lastTime = 0;
+
+
+// LOOKUP TABLE SINE
+uint16_t sine[361];
+
+
+void setup()
+{
+  Serial.begin(115200);
+
+  // fill table with sinus values for fast lookup
+  for (int i = 0; i < 361; i++)
+  {
+    sine[i] = 2047 + round(2047 * sin(i * PI / 180));
+  }
+
+
+  MCP.selectSPI();    //select SPI
+  //MCP.selectSPI1();   //select SPI1
+
+  MCP.begin(17);    // select pin = 17, SPI
+  //MCP.begin(13);    // select pin = 13, SPI1
+
+
+  MCP.fastWriteA(0);
+
+  period = 1e6 / freq;
+  halvePeriod = period / 2;
+
+  while (1)
+  {
+    // Serial.println(analogRead(A0));   // read output back via A0.
+    yield();
+    uint32_t now = micros();
+
+    count++;
+
+    if (now - lastTime > 100000)
+    {
+      lastTime = now;
+      // Serial.println(count); // show # updates per 0.1 second
+      count = 0;
+      if (Serial.available())
+      {
+        int c = Serial.read();
+        switch (c)
+        {
+          case '+':
+            freq++;
+            break;
+          case '-':
+            freq--;
+            break;
+          case '*':
+            freq *= 10;
+            break;
+          case '/':
+            freq /= 10;
+            break;
+          case '0' ... '9':
+            freq *= 10;
+            freq += (c - '0');
+            break;
+          case 'c':
+            freq = 0;
+            break;
+          case 'A':
+            break;
+          case 'a':
+            break;
+          case 'q':
+          case 's':
+          case 'w':
+          case 't':
+          case 'r':
+          case 'z':
+          case 'm':
+          case 'h':
+            mode = c;
+            break;
+          default:
+            break;
+        }
+        period = 1e6 / freq;
+        halvePeriod = period / 2;
+        Serial.print(freq);
+        //        Serial.print('\t');
+        //        Serial.print(period);
+        //        Serial.print('\t');
+        //        Serial.print(halvePeriod);
+        Serial.println();
+      }
+    }
+
+    uint32_t t = now % period;
+
+    switch (mode)
+    {
+      case 'q':
+        if (t < halvePeriod ) MCP.fastWriteA(4095);
+        else MCP.fastWriteA(0);
+        break;
+      case 'w':
+        MCP.fastWriteA(t * 4095 / period );
+        break;
+      case 't':
+        if (t < halvePeriod) MCP.fastWriteA(t * 4095 / halvePeriod);
+        else MCP.fastWriteA( (period - t) * 4095 / halvePeriod );
+        break;
+      case 'r':
+        MCP.fastWriteA(random(4096));
+        break;
+      case 'z':  // zero
+        MCP.fastWriteA(0);
+        break;
+      case 'h':  // high
+        MCP.fastWriteA(4095);
+        break;
+      case 'm':  // mid
+        MCP.fastWriteA(2047);
+        break;
+      default:
+      case 's':
+        // reference
+        // float f = ((PI * 2) * t)/period;
+        // MCP.setValue(2047 + 2047 * sin(f));
+        //
+        int idx = (360 * t) / period;
+        MCP.fastWriteA(sine[idx]);  // lookuptable
+        break;
+    }
+  }
+}
+
+
+void loop()
+{
+}
+
+
+// -- END OF FILE --
diff --git a/examples/readme.md b/examples/readme.md
index 1aedf22..3e94ace 100644
--- a/examples/readme.md
+++ b/examples/readme.md
@@ -2,11 +2,13 @@
 
 Note that some examples are ESP32 specific as they use e.g. VSPI() 
 
-|  example               |  UNO  | ESP32 |
-|:-----------------------|:-----:|:-----:|
-| MCP4911_test           |   Y   |   Y   |
-| MCP4921_standalone     |   Y   |   Y   |
-| MCP4921_test           |   Y   |   Y   |
-| MCP4921_VSPI           |   N   |   Y   |
-| MCP4921_wave_generator |   N   |   Y   |
+|  example                      |  UNO  | ESP32 | RP2040 |
+|:-----------------------------:|:-----:|:-----:|:------:|
+| MCP4911_test                  |   Y   |   Y   |    Y   |
+| MCP4921_standalone            |   Y   |   Y   |    Y   |
+| MCP4921_test                  |   Y   |   Y   |    Y   |
+| MCP4921_VSPI                  |   N   |   Y   |    N   |
+| MCP4921_wave_generator        |   Y   |   Y   |    Y   |
+| MCP4921_wave_generator_ESP32  |   N   |   Y   |    N   |
+| MCP4921_wave_generator_RP2040 |   N   |   N   |    Y   |