diff --git a/libraries/DAC8552/CHANGELOG.md b/libraries/DAC8552/CHANGELOG.md
index 6155128a..1a0ca635 100644
--- a/libraries/DAC8552/CHANGELOG.md
+++ b/libraries/DAC8552/CHANGELOG.md
@@ -6,6 +6,10 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/)
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
 
+## [0.5.1] - 2024-05-22
+- improve support for ARDUINO_ARCH_MBED
+
+
 ## [0.5.0] - 2024-01-20
 - Fix #16, improve handling SPI dependency.
 - update examples
diff --git a/libraries/DAC8552/DAC8552.cpp b/libraries/DAC8552/DAC8552.cpp
index ad492db4..8c3994e2 100644
--- a/libraries/DAC8552/DAC8552.cpp
+++ b/libraries/DAC8552/DAC8552.cpp
@@ -2,7 +2,7 @@
 //    FILE: DAC8552.cpp 
 //  AUTHOR: Rob Tillaart
 // PURPOSE: Arduino library for DAC8552 SPI Digital Analog Convertor
-// VERSION: 0.5.0
+// VERSION: 0.5.1
 //    DATE: 2017-12-14
 //     URL: https://github.com/RobTillaart/DAC8552
 
diff --git a/libraries/DAC8552/DAC8552.h b/libraries/DAC8552/DAC8552.h
index cacae87c..5bf35c5c 100644
--- a/libraries/DAC8552/DAC8552.h
+++ b/libraries/DAC8552/DAC8552.h
@@ -3,7 +3,7 @@
 //    FILE: DAC8552.h
 //  AUTHOR: Rob Tillaart
 // PURPOSE: Arduino library for DAC8552 SPI Digital Analog Convertor  
-// VERSION: 0.5.0
+// VERSION: 0.5.1
 //    DATE: 2017-12-14
 //     URL: https://github.com/RobTillaart/DAC8552
 
@@ -12,7 +12,7 @@
 #include "SPI.h"
 
 
-#define DAC8552_LIB_VERSION           (F("0.5.0"))
+#define DAC8552_LIB_VERSION           (F("0.5.1"))
 
 
 #define DAC8552_POWERDOWN_NORMAL      0
@@ -22,7 +22,10 @@
 
 
 #ifndef __SPI_CLASS__
-  #if defined(ARDUINO_ARCH_RP2040)
+  //  MBED must be tested before RP2040
+  #if defined(ARDUINO_ARCH_MBED)
+  #define __SPI_CLASS__   SPIClass
+  #elif defined(ARDUINO_ARCH_RP2040)
   #define __SPI_CLASS__   SPIClassRP2040
   #else
   #define __SPI_CLASS__   SPIClass
diff --git a/libraries/DAC8552/library.json b/libraries/DAC8552/library.json
index be8d05d8..579bd5f0 100644
--- a/libraries/DAC8552/library.json
+++ b/libraries/DAC8552/library.json
@@ -15,7 +15,7 @@
     "type": "git",
     "url": "https://github.com/RobTillaart/DAC8552"
   },
-  "version": "0.5.0",
+  "version": "0.5.1",
   "license": "MIT",
   "frameworks": "*",
   "platforms": "*",
diff --git a/libraries/DAC8552/library.properties b/libraries/DAC8552/library.properties
index c52356da..c2621d54 100644
--- a/libraries/DAC8552/library.properties
+++ b/libraries/DAC8552/library.properties
@@ -1,5 +1,5 @@
 name=DAC8552
-version=0.5.0
+version=0.5.1
 author=Rob Tillaart <rob.tillaart@gmail.com>
 maintainer=Rob Tillaart <rob.tillaart@gmail.com>
 sentence=Arduino library for DAC8532 and DAC8552 SPI Digital Analog Convertor.