Added missing (dummy) functions attach and detach interrupt to SPIClass (taken from SAM version), and added hooks.c for yield function. Note. use of yield() at the moment isn't possible, because the linker seems unable to find the function even though hooks.c is being compiled

STM32F1XX/cores/maple/Arduino.h

@@ -31,5 +31,6 @@
 
 void setup();
 void loop();
+void yield(void);
 
 #endif

STM32F1XX/cores/maple/hooks.c

@@ -0,0 +1,31 @@
+/*
+  Copyright (c) 2012 Arduino.  All right reserved.
+
+  This library is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  This library is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the GNU Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+*/
+
+/**
+ * Empty yield() hook.
+ *
+ * This function is intended to be used by library writers to build
+ * libraries or sketches that supports cooperative threads.
+ *
+ * Its defined as a weak symbol and it can be redefined to implement a
+ * real cooperative scheduler.
+ */
+static void __empty() {
+	// Empty
+}
+void yield(void) __attribute__ ((weak, alias("__empty")));

STM32F1XX/libraries/SPI/src/SPI.cpp

@@ -286,6 +286,14 @@ uint8 SPIClass::transfer(uint8 byte) {
     return this->read();
 }
 
+void SPIClass::attachInterrupt(void) {
+	// Should be enableInterrupt()
+}
+
+void SPIClass::detachInterrupt(void) {
+	// Should be disableInterrupt()
+}
+
 /*
  * Pin accessors
  */

STM32F1XX/libraries/SPI/src/SPI.h

@@ -191,6 +191,11 @@ public:
 	void setBitOrder(uint8_t bitOrder);	
 	void setdataMode(uint8_t dataMode);		
 	
+	// SPI Configuration methods
+	void attachInterrupt(void);
+	void detachInterrupt(void);
+	
+	
     /*
      * I/O
      */