Merge pull request #15 from FrankBoesing/144MHz-only

+Overclock 144 MHz only

README.md

 
 http://www.pjrc.com/teensy/td_download.html
 
+This version implements overclock to 120MHz, 144MHz and 168MHz.
+
+Howto:
+1. Overwrite Arduino\hardware\teensy\boards.txt with this version 
+2. Overwrite all in core/teensy3 with this version
+
+
 
 

teensy3/core_pins.h

 static inline void delayMicroseconds(uint32_t) __attribute__((always_inline, unused));
 static inline void delayMicroseconds(uint32_t usec)
 {
-#if F_CPU == 96000000
+#if F_CPU == 144000000
+	uint32_t n = usec * 48; 
+#elif F_CPU == 96000000
 	uint32_t n = usec << 5;
 #elif F_CPU == 48000000
 	uint32_t n = usec << 4;

teensy3/mk20dx128.c

 extern unsigned long _estack;
 //extern void __init_array_start(void);
 //extern void __init_array_end(void);
+
+
+
 extern int main (void);
 void ResetHandler(void);
 void _init_Teensyduino_internal_(void);
 	// now we're in FBE mode
 	// config PLL input for 16 MHz Crystal / 4 = 4 MHz
 	MCG_C5 = MCG_C5_PRDIV0(3);
-	// config PLL for 96 MHz output
-	MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(0);
+	
+#if F_CPU == 144000000	
+	MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(12); // config PLL for 144 MHz output
+#else
+	MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(0); // config PLL for 96 MHz output
+#endif
 	// wait for PLL to start using xtal as its input
 	while (!(MCG_S & MCG_S_PLLST)) ;
 	// wait for PLL to lock
 	while (!(MCG_S & MCG_S_LOCK0)) ;
 	// now we're in PBE mode
-#if F_CPU == 96000000
+
+#if F_CPU == 144000000
+	// config divisors: 144 MHz core, 48 MHz bus, 24 MHz flash
+	SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(2) |	 SIM_CLKDIV1_OUTDIV4(5); 
+#elif F_CPU == 96000000
 	// config divisors: 96 MHz core, 48 MHz bus, 24 MHz flash
 	SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(1) |	 SIM_CLKDIV1_OUTDIV4(3);
 #elif F_CPU == 48000000
 	// config divisors: 24 MHz core, 24 MHz bus, 24 MHz flash
 	SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(3) | SIM_CLKDIV1_OUTDIV2(3) |	 SIM_CLKDIV1_OUTDIV4(3);
 #else
-#error "Error, F_CPU must be 96000000, 48000000, or 24000000"
+#error "Error, F_CPU must be  144000000, 96000000, 48000000, or 24000000"
 #endif
 	// switch to PLL as clock source, FLL input = 16 MHz / 512
 	MCG_C1 = MCG_C1_CLKS(0) | MCG_C1_FRDIV(4);
 	while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(3)) ;
 	// now we're in PEE mode
 	// configure USB for 48 MHz clock
+#if F_CPU == 144000000
+	SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(2); // USB = 144 MHz PLL / 3
+#else
 	SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(1); // USB = 96 MHz PLL / 2
+#endif	
 	// USB uses PLL clock, trace is CPU clock, CLKOUT=OSCERCLK0
 	SIM_SOPT2 = SIM_SOPT2_USBSRC | SIM_SOPT2_PLLFLLSEL | SIM_SOPT2_TRACECLKSEL | SIM_SOPT2_CLKOUTSEL(6);
 

teensy3/mk20dx128.h

 //#define F_BUS 24000000
 //#define F_MEM 24000000
 
-#if (F_CPU == 96000000)
+#if (F_CPU == 144000000)
+ #define F_BUS 48000000
+ #define F_MEM 24000000
+#elif (F_CPU == 96000000)
  #define F_BUS 48000000
  #define F_MEM 24000000
 #elif (F_CPU == 48000000)

teensy3/pins_teensy.c

 #if F_BUS == 48000000
 #define DEFAULT_FTM_MOD (49152 - 1)
 #define DEFAULT_FTM_PRESCALE 1
-#else
+#elif F_BUS == 24000000
 #define DEFAULT_FTM_MOD (49152 - 1)
 #define DEFAULT_FTM_PRESCALE 0
 #endif
 	}
 }
 
-#if F_CPU == 96000000
+#if F_CPU == 144000000
+#define PULSEIN_LOOPS_PER_USEC 21  
+#elif F_CPU == 96000000
 #define PULSEIN_LOOPS_PER_USEC 14
 #elif F_CPU == 48000000
 #define PULSEIN_LOOPS_PER_USEC 7

teensy3/usb_seremu.c

 // software.  If it's too long, we stall the user's program when no software is running.
 #define TX_TIMEOUT_MSEC 30
 
-#if F_CPU == 96000000
+#if F_CPU == 144000000
+  #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 932) 
+#elif F_CPU == 96000000
   #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 596)
 #elif F_CPU == 48000000
   #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 428)

teensy3/usb_serial.c

 // software.  If it's too long, we stall the user's program when no software is running.
 #define TX_TIMEOUT_MSEC 70
 
-#if F_CPU == 96000000
+#if F_CPU == 144000000
+  #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 932) 
+#elif F_CPU == 96000000
   #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 596)
 #elif F_CPU == 48000000
   #define TX_TIMEOUT (TX_TIMEOUT_MSEC * 428)