Add macro for portInputRegister()

Author: James Foster

SampleProjects/TestSomething/test/outputRegister.cpp

@@ -21,6 +21,23 @@ unittest(portOutputRegister)
   *(ss_pin_reg) |= ss_pin_mask;               // clear SS
   assertEqual((int) 1, (int) *ss_pin_reg);    // verify value
 }
+
+unittest(portInputRegister)
+{
+  uint8_t ss_pin = 12;
+  uint8_t ss_port = digitalPinToPort(ss_pin);
+  assertEqual(12, ss_port);
+  uint8_t *ss_pin_reg = portInputRegister(ss_port);
+  assertEqual(GODMODE()->pMmapPort(ss_port), ss_pin_reg);
+  uint8_t ss_pin_mask = digitalPinToBitMask(ss_pin);
+  assertEqual(1, ss_pin_mask);
+
+  assertEqual((int) 1, (int) *ss_pin_reg);    // verify initial value
+  *(ss_pin_reg) &= ~ss_pin_mask;              // set SS
+  assertEqual((int) 0, (int) *ss_pin_reg);    // verify value
+  *(ss_pin_reg) |= ss_pin_mask;               // clear SS
+  assertEqual((int) 1, (int) *ss_pin_reg);    // verify value
+}
 #endif
 
 unittest_main()

cpp/arduino/Godmode.h

@@ -182,6 +182,7 @@ inline void noTone(uint8_t _pin) {}
 #if defined(__AVR__)
   #define digitalPinToBitMask(pin)  (1)
   #define digitalPinToPort(pin)     (pin)
+  #define portInputRegister(port)   (GODMODE()->pMmapPort(port))
   #define portOutputRegister(port)  (GODMODE()->pMmapPort(port))
 #else
   // we don't (yet) support other boards