Merge pull request arduino#134 from beeryt/patch-1

Wiring: Clean up repeated pin description access

Author: ladyada

cores/arduino/wiring_digital.c

@@ -30,39 +30,43 @@ void pinMode( uint32_t ulPin, uint32_t ulMode )
     return ;
   }
 
+  EPortType port = g_APinDescription[ulPin].ulPort;
+  uint32_t pin = g_APinDescription[ulPin].ulPin;
+  uint32_t pinMask = (1ul << pin);
+
   // Set pin mode according to chapter '22.6.3 I/O Pin Configuration'
   switch ( ulMode )
   {
     case INPUT:
       // Set pin to input mode
-      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
-      PORT->Group[g_APinDescription[ulPin].ulPort].DIRCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
+      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
+      PORT->Group[port].DIRCLR.reg = pinMask ;
     break ;
 
     case INPUT_PULLUP:
       // Set pin to input mode with pull-up resistor enabled
-      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
-      PORT->Group[g_APinDescription[ulPin].ulPort].DIRCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
+      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
+      PORT->Group[port].DIRCLR.reg = pinMask ;
 
       // Enable pull level (cf '22.6.3.2 Input Configuration' and '22.8.7 Data Output Value Set')
-      PORT->Group[g_APinDescription[ulPin].ulPort].OUTSET.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
+      PORT->Group[port].OUTSET.reg = pinMask ;
     break ;
 
     case INPUT_PULLDOWN:
       // Set pin to input mode with pull-down resistor enabled
-      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
-      PORT->Group[g_APinDescription[ulPin].ulPort].DIRCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
+      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN|PORT_PINCFG_PULLEN) ;
+      PORT->Group[port].DIRCLR.reg = pinMask ;
 
       // Enable pull level (cf '22.6.3.2 Input Configuration' and '22.8.6 Data Output Value Clear')
-      PORT->Group[g_APinDescription[ulPin].ulPort].OUTCLR.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
+      PORT->Group[port].OUTCLR.reg = pinMask ;
     break ;
 
     case OUTPUT:
       // enable input, to support reading back values, with pullups disabled
-      PORT->Group[g_APinDescription[ulPin].ulPort].PINCFG[g_APinDescription[ulPin].ulPin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
+      PORT->Group[port].PINCFG[pin].reg=(uint8_t)(PORT_PINCFG_INEN) ;
 
       // Set pin to output mode
-      PORT->Group[g_APinDescription[ulPin].ulPort].DIRSET.reg = (uint32_t)(1<<g_APinDescription[ulPin].ulPin) ;
+      PORT->Group[port].DIRSET.reg = pinMask ;
     break ;
 
     default: