1 /* Teensyduino Core Library
2 * http://www.pjrc.com/teensy/
3 * Copyright (c) 2013 PJRC.COM, LLC.
5 * Permission is hereby granted, free of charge, to any person obtaining
6 * a copy of this software and associated documentation files (the
7 * "Software"), to deal in the Software without restriction, including
8 * without limitation the rights to use, copy, modify, merge, publish,
9 * distribute, sublicense, and/or sell copies of the Software, and to
10 * permit persons to whom the Software is furnished to do so, subject to
11 * the following conditions:
13 * 1. The above copyright notice and this permission notice shall be
14 * included in all copies or substantial portions of the Software.
16 * 2. If the Software is incorporated into a build system that allows
17 * selection among a list of target devices, then similar target
18 * devices manufactured by PJRC.COM must be included in the list of
19 * target devices and selectable in the same manner.
21 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
25 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
26 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
27 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
34 extern unsigned long _stext;
35 extern unsigned long _etext;
36 extern unsigned long _sdata;
37 extern unsigned long _edata;
38 extern unsigned long _sbss;
39 extern unsigned long _ebss;
40 extern unsigned long _estack;
41 //extern void __init_array_start(void);
42 //extern void __init_array_end(void);
46 extern int main (void);
47 void ResetHandler(void);
48 void _init_Teensyduino_internal_(void);
49 void __libc_init_array(void);
55 // keep polling some communication while in fault
56 // mode, so we don't completely die.
57 if (SIM_SCGC4 & SIM_SCGC4_USBOTG) usb_isr();
58 if (SIM_SCGC4 & SIM_SCGC4_UART0) uart0_status_isr();
59 if (SIM_SCGC4 & SIM_SCGC4_UART1) uart1_status_isr();
60 if (SIM_SCGC4 & SIM_SCGC4_UART2) uart2_status_isr();
69 extern volatile uint32_t systick_millis_count;
70 void systick_default_isr(void)
72 systick_millis_count++;
75 void nmi_isr(void) __attribute__ ((weak, alias("unused_isr")));
76 void hard_fault_isr(void) __attribute__ ((weak, alias("unused_isr")));
77 void memmanage_fault_isr(void) __attribute__ ((weak, alias("unused_isr")));
78 void bus_fault_isr(void) __attribute__ ((weak, alias("unused_isr")));
79 void usage_fault_isr(void) __attribute__ ((weak, alias("unused_isr")));
80 void svcall_isr(void) __attribute__ ((weak, alias("unused_isr")));
81 void debugmonitor_isr(void) __attribute__ ((weak, alias("unused_isr")));
82 void pendablesrvreq_isr(void) __attribute__ ((weak, alias("unused_isr")));
83 void systick_isr(void) __attribute__ ((weak, alias("systick_default_isr")));
85 void dma_ch0_isr(void) __attribute__ ((weak, alias("unused_isr")));
86 void dma_ch1_isr(void) __attribute__ ((weak, alias("unused_isr")));
87 void dma_ch2_isr(void) __attribute__ ((weak, alias("unused_isr")));
88 void dma_ch3_isr(void) __attribute__ ((weak, alias("unused_isr")));
89 void dma_ch4_isr(void) __attribute__ ((weak, alias("unused_isr")));
90 void dma_ch5_isr(void) __attribute__ ((weak, alias("unused_isr")));
91 void dma_ch6_isr(void) __attribute__ ((weak, alias("unused_isr")));
92 void dma_ch7_isr(void) __attribute__ ((weak, alias("unused_isr")));
93 void dma_ch8_isr(void) __attribute__ ((weak, alias("unused_isr")));
94 void dma_ch9_isr(void) __attribute__ ((weak, alias("unused_isr")));
95 void dma_ch10_isr(void) __attribute__ ((weak, alias("unused_isr")));
96 void dma_ch11_isr(void) __attribute__ ((weak, alias("unused_isr")));
97 void dma_ch12_isr(void) __attribute__ ((weak, alias("unused_isr")));
98 void dma_ch13_isr(void) __attribute__ ((weak, alias("unused_isr")));
99 void dma_ch14_isr(void) __attribute__ ((weak, alias("unused_isr")));
100 void dma_ch15_isr(void) __attribute__ ((weak, alias("unused_isr")));
101 void dma_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
102 void mcm_isr(void) __attribute__ ((weak, alias("unused_isr")));
103 void flash_cmd_isr(void) __attribute__ ((weak, alias("unused_isr")));
104 void flash_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
105 void low_voltage_isr(void) __attribute__ ((weak, alias("unused_isr")));
106 void wakeup_isr(void) __attribute__ ((weak, alias("unused_isr")));
107 void watchdog_isr(void) __attribute__ ((weak, alias("unused_isr")));
108 void i2c0_isr(void) __attribute__ ((weak, alias("unused_isr")));
109 void i2c1_isr(void) __attribute__ ((weak, alias("unused_isr")));
110 void i2c2_isr(void) __attribute__ ((weak, alias("unused_isr")));
111 void spi0_isr(void) __attribute__ ((weak, alias("unused_isr")));
112 void spi1_isr(void) __attribute__ ((weak, alias("unused_isr")));
113 void spi2_isr(void) __attribute__ ((weak, alias("unused_isr")));
114 void sdhc_isr(void) __attribute__ ((weak, alias("unused_isr")));
115 void can0_message_isr(void) __attribute__ ((weak, alias("unused_isr")));
116 void can0_bus_off_isr(void) __attribute__ ((weak, alias("unused_isr")));
117 void can0_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
118 void can0_tx_warn_isr(void) __attribute__ ((weak, alias("unused_isr")));
119 void can0_rx_warn_isr(void) __attribute__ ((weak, alias("unused_isr")));
120 void can0_wakeup_isr(void) __attribute__ ((weak, alias("unused_isr")));
121 void i2s0_tx_isr(void) __attribute__ ((weak, alias("unused_isr")));
122 void i2s0_rx_isr(void) __attribute__ ((weak, alias("unused_isr")));
123 void uart0_lon_isr(void) __attribute__ ((weak, alias("unused_isr")));
124 void uart0_status_isr(void) __attribute__ ((weak, alias("unused_isr")));
125 void uart0_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
126 void uart1_status_isr(void) __attribute__ ((weak, alias("unused_isr")));
127 void uart1_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
128 void uart2_status_isr(void) __attribute__ ((weak, alias("unused_isr")));
129 void uart2_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
130 void uart3_status_isr(void) __attribute__ ((weak, alias("unused_isr")));
131 void uart3_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
132 void uart4_status_isr(void) __attribute__ ((weak, alias("unused_isr")));
133 void uart4_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
134 void uart5_status_isr(void) __attribute__ ((weak, alias("unused_isr")));
135 void uart5_error_isr(void) __attribute__ ((weak, alias("unused_isr")));
136 void adc0_isr(void) __attribute__ ((weak, alias("unused_isr")));
137 void adc1_isr(void) __attribute__ ((weak, alias("unused_isr")));
138 void cmp0_isr(void) __attribute__ ((weak, alias("unused_isr")));
139 void cmp1_isr(void) __attribute__ ((weak, alias("unused_isr")));
140 void cmp2_isr(void) __attribute__ ((weak, alias("unused_isr")));
141 void ftm0_isr(void) __attribute__ ((weak, alias("unused_isr")));
142 void ftm1_isr(void) __attribute__ ((weak, alias("unused_isr")));
143 void ftm2_isr(void) __attribute__ ((weak, alias("unused_isr")));
144 void ftm3_isr(void) __attribute__ ((weak, alias("unused_isr")));
145 void cmt_isr(void) __attribute__ ((weak, alias("unused_isr")));
146 void rtc_alarm_isr(void) __attribute__ ((weak, alias("unused_isr")));
147 void rtc_seconds_isr(void) __attribute__ ((weak, alias("unused_isr")));
148 void pit0_isr(void) __attribute__ ((weak, alias("unused_isr")));
149 void pit1_isr(void) __attribute__ ((weak, alias("unused_isr")));
150 void pit2_isr(void) __attribute__ ((weak, alias("unused_isr")));
151 void pit3_isr(void) __attribute__ ((weak, alias("unused_isr")));
152 void pdb_isr(void) __attribute__ ((weak, alias("unused_isr")));
153 void usb_isr(void) __attribute__ ((weak, alias("unused_isr")));
154 void usb_charge_isr(void) __attribute__ ((weak, alias("unused_isr")));
155 void dac0_isr(void) __attribute__ ((weak, alias("unused_isr")));
156 void dac1_isr(void) __attribute__ ((weak, alias("unused_isr")));
157 void tsi0_isr(void) __attribute__ ((weak, alias("unused_isr")));
158 void mcg_isr(void) __attribute__ ((weak, alias("unused_isr")));
159 void lptmr_isr(void) __attribute__ ((weak, alias("unused_isr")));
160 void porta_isr(void) __attribute__ ((weak, alias("unused_isr")));
161 void portb_isr(void) __attribute__ ((weak, alias("unused_isr")));
162 void portc_isr(void) __attribute__ ((weak, alias("unused_isr")));
163 void portd_isr(void) __attribute__ ((weak, alias("unused_isr")));
164 void porte_isr(void) __attribute__ ((weak, alias("unused_isr")));
165 void software_isr(void) __attribute__ ((weak, alias("unused_isr")));
167 #if defined(__MK20DX128__)
168 __attribute__ ((section(".dmabuffers"), used, aligned(256)))
170 __attribute__ ((section(".dmabuffers"), used, aligned(512)))
172 void (* _VectorsRam[NVIC_NUM_INTERRUPTS+16])(void);
174 __attribute__ ((section(".vectors"), used))
175 void (* const _VectorsFlash[NVIC_NUM_INTERRUPTS+16])(void) =
177 (void (*)(void))((unsigned long)&_estack), // 0 ARM: Initial Stack Pointer
178 ResetHandler, // 1 ARM: Initial Program Counter
179 nmi_isr, // 2 ARM: Non-maskable Interrupt (NMI)
180 hard_fault_isr, // 3 ARM: Hard Fault
181 memmanage_fault_isr, // 4 ARM: MemManage Fault
182 bus_fault_isr, // 5 ARM: Bus Fault
183 usage_fault_isr, // 6 ARM: Usage Fault
188 svcall_isr, // 11 ARM: Supervisor call (SVCall)
189 debugmonitor_isr, // 12 ARM: Debug Monitor
191 pendablesrvreq_isr, // 14 ARM: Pendable req serv(PendableSrvReq)
192 systick_isr, // 15 ARM: System tick timer (SysTick)
193 #if defined(__MK20DX128__)
194 dma_ch0_isr, // 16 DMA channel 0 transfer complete
195 dma_ch1_isr, // 17 DMA channel 1 transfer complete
196 dma_ch2_isr, // 18 DMA channel 2 transfer complete
197 dma_ch3_isr, // 19 DMA channel 3 transfer complete
198 dma_error_isr, // 20 DMA error interrupt channel
199 unused_isr, // 21 DMA --
200 flash_cmd_isr, // 22 Flash Memory Command complete
201 flash_error_isr, // 23 Flash Read collision
202 low_voltage_isr, // 24 Low-voltage detect/warning
203 wakeup_isr, // 25 Low Leakage Wakeup
204 watchdog_isr, // 26 Both EWM and WDOG interrupt
207 i2s0_tx_isr, // 29 I2S0 Transmit
208 i2s0_rx_isr, // 30 I2S0 Receive
209 uart0_lon_isr, // 31 UART0 CEA709.1-B (LON) status
210 uart0_status_isr, // 32 UART0 status
211 uart0_error_isr, // 33 UART0 error
212 uart1_status_isr, // 34 UART1 status
213 uart1_error_isr, // 35 UART1 error
214 uart2_status_isr, // 36 UART2 status
215 uart2_error_isr, // 37 UART2 error
222 rtc_alarm_isr, // 44 RTC Alarm interrupt
223 rtc_seconds_isr, // 45 RTC Seconds interrupt
224 pit0_isr, // 46 PIT Channel 0
225 pit1_isr, // 47 PIT Channel 1
226 pit2_isr, // 48 PIT Channel 2
227 pit3_isr, // 49 PIT Channel 3
228 pdb_isr, // 50 PDB Programmable Delay Block
229 usb_isr, // 51 USB OTG
230 usb_charge_isr, // 52 USB Charger Detect
233 lptmr_isr, // 55 Low Power Timer
234 porta_isr, // 56 Pin detect (Port A)
235 portb_isr, // 57 Pin detect (Port B)
236 portc_isr, // 58 Pin detect (Port C)
237 portd_isr, // 59 Pin detect (Port D)
238 porte_isr, // 60 Pin detect (Port E)
239 software_isr, // 61 Software interrupt
240 #elif defined(__MK20DX256__)
241 dma_ch0_isr, // 16 DMA channel 0 transfer complete
242 dma_ch1_isr, // 17 DMA channel 1 transfer complete
243 dma_ch2_isr, // 18 DMA channel 2 transfer complete
244 dma_ch3_isr, // 19 DMA channel 3 transfer complete
245 dma_ch4_isr, // 20 DMA channel 4 transfer complete
246 dma_ch5_isr, // 21 DMA channel 5 transfer complete
247 dma_ch6_isr, // 22 DMA channel 6 transfer complete
248 dma_ch7_isr, // 23 DMA channel 7 transfer complete
249 dma_ch8_isr, // 24 DMA channel 8 transfer complete
250 dma_ch9_isr, // 25 DMA channel 9 transfer complete
251 dma_ch10_isr, // 26 DMA channel 10 transfer complete
252 dma_ch11_isr, // 27 DMA channel 10 transfer complete
253 dma_ch12_isr, // 28 DMA channel 10 transfer complete
254 dma_ch13_isr, // 29 DMA channel 10 transfer complete
255 dma_ch14_isr, // 30 DMA channel 10 transfer complete
256 dma_ch15_isr, // 31 DMA channel 10 transfer complete
257 dma_error_isr, // 32 DMA error interrupt channel
259 flash_cmd_isr, // 34 Flash Memory Command complete
260 flash_error_isr, // 35 Flash Read collision
261 low_voltage_isr, // 36 Low-voltage detect/warning
262 wakeup_isr, // 37 Low Leakage Wakeup
263 watchdog_isr, // 38 Both EWM and WDOG interrupt
270 can0_message_isr, // 45 CAN OR'ed Message buffer (0-15)
271 can0_bus_off_isr, // 46 CAN Bus Off
272 can0_error_isr, // 47 CAN Error
273 can0_tx_warn_isr, // 48 CAN Transmit Warning
274 can0_rx_warn_isr, // 49 CAN Receive Warning
275 can0_wakeup_isr, // 50 CAN Wake Up
276 i2s0_tx_isr, // 51 I2S0 Transmit
277 i2s0_rx_isr, // 52 I2S0 Receive
285 uart0_lon_isr, // 60 UART0 CEA709.1-B (LON) status
286 uart0_status_isr, // 61 UART0 status
287 uart0_error_isr, // 62 UART0 error
288 uart1_status_isr, // 63 UART1 status
289 uart1_error_isr, // 64 UART1 error
290 uart2_status_isr, // 65 UART2 status
291 uart2_error_isr, // 66 UART2 error
307 rtc_alarm_isr, // 82 RTC Alarm interrupt
308 rtc_seconds_isr, // 83 RTC Seconds interrupt
309 pit0_isr, // 84 PIT Channel 0
310 pit1_isr, // 85 PIT Channel 1
311 pit2_isr, // 86 PIT Channel 2
312 pit3_isr, // 87 PIT Channel 3
313 pdb_isr, // 88 PDB Programmable Delay Block
314 usb_isr, // 89 USB OTG
315 usb_charge_isr, // 90 USB Charger Detect
326 lptmr_isr, // 101 Low Power Timer
327 unused_isr, // 102 --
328 porta_isr, // 103 Pin detect (Port A)
329 portb_isr, // 104 Pin detect (Port B)
330 portc_isr, // 105 Pin detect (Port C)
331 portd_isr, // 106 Pin detect (Port D)
332 porte_isr, // 107 Pin detect (Port E)
333 unused_isr, // 108 --
334 unused_isr, // 109 --
335 software_isr, // 110 Software interrupt
343 __attribute__ ((section(".flashconfig"), used))
344 const uint8_t flashconfigbytes[16] = {
345 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF,
346 0xFF, 0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF
350 // Automatically initialize the RTC. When the build defines the compile
351 // time, and the user has added a crystal, the RTC will automatically
352 // begin at the time of the first upload.
354 #define TIME_T 1349049600 // default 1 Oct 2012 (never used, Arduino sets this)
356 extern void rtc_set(unsigned long t);
359 static void startup_default_early_hook(void) { WDOG_STCTRLH = WDOG_STCTRLH_ALLOWUPDATE; }
360 static void startup_default_late_hook(void) {}
361 void startup_early_hook(void) __attribute__ ((weak, alias("startup_default_early_hook")));
362 void startup_late_hook(void) __attribute__ ((weak, alias("startup_default_late_hook")));
364 __attribute__ ((section(".startup")))
365 void ResetHandler(void)
367 uint32_t *src = &_etext;
368 uint32_t *dest = &_sdata;
374 WDOG_UNLOCK = WDOG_UNLOCK_SEQ1;
375 WDOG_UNLOCK = WDOG_UNLOCK_SEQ2;
376 __asm__ volatile ("nop");
377 __asm__ volatile ("nop");
378 // programs using the watchdog timer or needing to initialize hardware as
379 // early as possible can implement startup_early_hook()
380 startup_early_hook();
382 // enable clocks to always-used peripherals
383 #if defined(__MK20DX128__)
384 SIM_SCGC5 = 0x00043F82; // clocks active to all GPIO
385 SIM_SCGC6 = SIM_SCGC6_RTC | SIM_SCGC6_FTM0 | SIM_SCGC6_FTM1 | SIM_SCGC6_ADC0 | SIM_SCGC6_FTFL;
386 #elif defined(__MK20DX256__)
387 SIM_SCGC3 = SIM_SCGC3_ADC1 | SIM_SCGC3_FTM2;
388 SIM_SCGC5 = 0x00043F82; // clocks active to all GPIO
389 SIM_SCGC6 = SIM_SCGC6_RTC | SIM_SCGC6_FTM0 | SIM_SCGC6_FTM1 | SIM_SCGC6_ADC0 | SIM_SCGC6_FTFL;
391 // if the RTC oscillator isn't enabled, get it started early
392 if (!(RTC_CR & RTC_CR_OSCE)) {
394 RTC_CR = RTC_CR_SC16P | RTC_CR_SC4P | RTC_CR_OSCE;
397 // release I/O pins hold, if we woke up from VLLS mode
398 if (PMC_REGSC & PMC_REGSC_ACKISO) PMC_REGSC |= PMC_REGSC_ACKISO;
400 // since this is a write once register, make it visible to all F_CPU's
401 // so we can into other sleep modes in the future at any speed
402 SMC_PMPROT = SMC_PMPROT_AVLP | SMC_PMPROT_ALLS | SMC_PMPROT_AVLLS;
404 // TODO: do this while the PLL is waiting to lock....
405 while (dest < &_edata) *dest++ = *src++;
407 while (dest < &_ebss) *dest++ = 0;
409 // default all interrupts to medium priority level
410 for (i=0; i < NVIC_NUM_INTERRUPTS + 16; i++) _VectorsRam[i] = _VectorsFlash[i];
411 for (i=0; i < NVIC_NUM_INTERRUPTS; i++) NVIC_SET_PRIORITY(i, 128);
412 SCB_VTOR = (uint32_t)_VectorsRam; // use vector table in RAM
414 // hardware always starts in FEI mode
415 // C1[CLKS] bits are written to 00
416 // C1[IREFS] bit is written to 1
417 // C6[PLLS] bit is written to 0
418 // MCG_SC[FCDIV] defaults to divide by two for internal ref clock
419 // I tried changing MSG_SC to divide by 1, it didn't work for me
421 // use the internal oscillator
422 MCG_C1 = MCG_C1_CLKS(1) | MCG_C1_IREFS;
423 // wait for MCGOUT to use oscillator
424 while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(1)) ;
425 for (n=0; n<10; n++) ; // TODO: why do we get 2 mA extra without this delay?
426 MCG_C2 = MCG_C2_IRCS;
427 while (!(MCG_S & MCG_S_IRCST)) ;
429 // C1[CLKS] bits are written to 01
430 // C1[IREFS] bit is written to 1
431 // C6[PLLS] is written to 0
432 // C2[LP] is written to 0
433 MCG_C2 = MCG_C2_IRCS | MCG_C2_LP;
435 // C1[CLKS] bits are written to 01
436 // C1[IREFS] bit is written to 1
437 // C6[PLLS] bit is written to 0
438 // C2[LP] bit is written to 1
440 // enable capacitors for crystal
441 OSC0_CR = OSC_SC8P | OSC_SC2P;
442 // enable osc, 8-32 MHz range, low power mode
443 MCG_C2 = MCG_C2_RANGE0(2) | MCG_C2_EREFS;
444 // switch to crystal as clock source, FLL input = 16 MHz / 512
445 MCG_C1 = MCG_C1_CLKS(2) | MCG_C1_FRDIV(4);
446 // wait for crystal oscillator to begin
447 while ((MCG_S & MCG_S_OSCINIT0) == 0) ;
448 // wait for FLL to use oscillator
449 while ((MCG_S & MCG_S_IREFST) != 0) ;
450 // wait for MCGOUT to use oscillator
451 while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(2)) ;
453 // C1[CLKS] bits are written to 10
454 // C1[IREFS] bit is written to 0
455 // C1[FRDIV] must be written to divide xtal to 31.25-39 kHz
456 // C6[PLLS] bit is written to 0
457 // C2[LP] is written to 0
458 #if F_CPU <= 16000000
459 // if the crystal is fast enough, use it directly (no FLL or PLL)
460 MCG_C2 = MCG_C2_RANGE0(2) | MCG_C2_EREFS | MCG_C2_LP;
462 // C1[CLKS] bits are written to 10
463 // C1[IREFS] bit is written to 0
464 // C2[LP] bit is written to 1
466 // if we need faster than the crystal, turn on the PLL
467 #if F_CPU == 72000000
468 MCG_C5 = MCG_C5_PRDIV0(5); // config PLL input for 16 MHz Crystal / 6 = 2.667 Hz
470 MCG_C5 = MCG_C5_PRDIV0(3); // config PLL input for 16 MHz Crystal / 4 = 4 MHz
472 #if F_CPU == 168000000
473 MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(18); // config PLL for 168 MHz output
474 #elif F_CPU == 144000000
475 MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(12); // config PLL for 144 MHz output
476 #elif F_CPU == 120000000
477 MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(6); // config PLL for 120 MHz output
478 #elif F_CPU == 72000000
479 MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(3); // config PLL for 72 MHz output
481 MCG_C6 = MCG_C6_PLLS | MCG_C6_VDIV0(0); // config PLL for 96 MHz output
483 // wait for PLL to start using xtal as its input
484 while (!(MCG_S & MCG_S_PLLST)) ;
485 // wait for PLL to lock
486 while (!(MCG_S & MCG_S_LOCK0)) ;
487 // now we're in PBE mode
491 // now program the clock dividers
492 #if F_CPU == 168000000
493 // config divisors: 168 MHz core, 56 MHz bus, 33.6 MHz flash, USB = 168 * 2 / 7
494 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(2) | SIM_CLKDIV1_OUTDIV4(4);
495 SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(6) | SIM_CLKDIV2_USBFRAC;
496 #elif F_CPU == 144000000
497 // config divisors: 144 MHz core, 48 MHz bus, 28.8 MHz flash, USB = 144 / 3
498 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(2) | SIM_CLKDIV1_OUTDIV4(4);
499 SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(2);
500 #elif F_CPU == 120000000
501 // config divisors: 120 MHz core, 60 MHz bus, 24 MHz flash, USB = 128 * 2 / 5
502 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(1) | SIM_CLKDIV1_OUTDIV4(4);
503 SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(4) | SIM_CLKDIV2_USBFRAC;
504 #elif F_CPU == 96000000
505 // config divisors: 96 MHz core, 48 MHz bus, 24 MHz flash, USB = 96 / 2
506 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(1) | SIM_CLKDIV1_OUTDIV4(3);
507 SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(1);
508 #elif F_CPU == 72000000
509 // config divisors: 72 MHz core, 36 MHz bus, 24 MHz flash, USB = 72 * 2 / 3
510 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(1) | SIM_CLKDIV1_OUTDIV4(2);
511 SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(2) | SIM_CLKDIV2_USBFRAC;
512 #elif F_CPU == 48000000
513 // config divisors: 48 MHz core, 48 MHz bus, 24 MHz flash, USB = 96 / 2
514 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(1) | SIM_CLKDIV1_OUTDIV2(1) | SIM_CLKDIV1_OUTDIV4(3);
515 SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(1);
516 #elif F_CPU == 24000000
517 // config divisors: 24 MHz core, 24 MHz bus, 24 MHz flash, USB = 96 / 2
518 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(3) | SIM_CLKDIV1_OUTDIV2(3) | SIM_CLKDIV1_OUTDIV4(3);
519 SIM_CLKDIV2 = SIM_CLKDIV2_USBDIV(1);
520 #elif F_CPU == 16000000
521 // config divisors: 16 MHz core, 16 MHz bus, 16 MHz flash
522 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(0) | SIM_CLKDIV1_OUTDIV4(0);
523 #elif F_CPU == 8000000
524 // config divisors: 8 MHz core, 8 MHz bus, 8 MHz flash
525 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(1) | SIM_CLKDIV1_OUTDIV2(1) | SIM_CLKDIV1_OUTDIV4(1);
526 #elif F_CPU == 4000000
527 // config divisors: 4 MHz core, 4 MHz bus, 2 MHz flash
528 // since we are running from external clock 16MHz
529 // fix outdiv too -> cpu 16/4, bus 16/4, flash 16/4
530 // here we can go into vlpr?
531 // config divisors: 4 MHz core, 4 MHz bus, 4 MHz flash
532 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(3) | SIM_CLKDIV1_OUTDIV2(3) | SIM_CLKDIV1_OUTDIV4(3);
533 #elif F_CPU == 2000000
534 // since we are running from the fast internal reference clock 4MHz
535 // but is divided down by 2 so we actually have a 2MHz, MCG_SC[FCDIV] default is 2
536 // fix outdiv -> cpu 2/1, bus 2/1, flash 2/2
537 // config divisors: 2 MHz core, 2 MHz bus, 1 MHz flash
538 SIM_CLKDIV1 = SIM_CLKDIV1_OUTDIV1(0) | SIM_CLKDIV1_OUTDIV2(0) | SIM_CLKDIV1_OUTDIV4(1);
540 #error "Error, F_CPU must be 168, 144, 120, 96, 72, 48, 24, 16, 8, 4, or 2 MHz"
544 // switch to PLL as clock source, FLL input = 16 MHz / 512
545 MCG_C1 = MCG_C1_CLKS(0) | MCG_C1_FRDIV(4);
546 // wait for PLL clock to be used
547 while ((MCG_S & MCG_S_CLKST_MASK) != MCG_S_CLKST(3)) ;
548 // now we're in PEE mode
549 // USB uses PLL clock, trace is CPU clock, CLKOUT=OSCERCLK0
550 SIM_SOPT2 = SIM_SOPT2_USBSRC | SIM_SOPT2_PLLFLLSEL | SIM_SOPT2_TRACECLKSEL | SIM_SOPT2_CLKOUTSEL(6);
552 SIM_SOPT2 = SIM_SOPT2_TRACECLKSEL | SIM_SOPT2_CLKOUTSEL(3);
556 // since we are not going into "stop mode" i removed it
557 SMC_PMCTRL = SMC_PMCTRL_RUNM(2); // VLPR mode :-)
560 // initialize the SysTick counter
561 SYST_RVR = (F_CPU / 1000) - 1;
562 SYST_CSR = SYST_CSR_CLKSOURCE | SYST_CSR_TICKINT | SYST_CSR_ENABLE;
567 _init_Teensyduino_internal_();
568 if (RTC_SR & RTC_SR_TIF) {
569 // TODO: this should probably set the time more agressively, if
570 // we could reliably detect the first reboot after programming.
581 char *__brkval = (char *)&_ebss;
583 void * _sbrk(int incr)
585 char *prev = __brkval;
590 __attribute__((weak))
591 int _read(int file, char *ptr, int len)
596 __attribute__((weak))
602 #include <sys/stat.h>
604 __attribute__((weak))
605 int _fstat(int fd, struct stat *st)
607 st->st_mode = S_IFCHR;
611 __attribute__((weak))
617 __attribute__((weak))
618 int _lseek(int fd, long long offset, int whence)
623 __attribute__((weak))
624 void _exit(int status)
629 __attribute__((weak))
630 void __cxa_pure_virtual()
635 __attribute__((weak))
636 int __cxa_guard_acquire (char *g)
641 __attribute__((weak))
642 void __cxa_guard_release(char *g)
647 int nvic_execution_priority(void)
650 uint32_t primask, faultmask, basepri, ipsr;
652 // full algorithm in ARM DDI0403D, page B1-639
653 // this isn't quite complete, but hopefully good enough
654 __asm__ volatile("mrs %0, faultmask\n" : "=r" (faultmask)::);
655 if (faultmask) return -1;
656 __asm__ volatile("mrs %0, primask\n" : "=r" (primask)::);
657 if (primask) return 0;
658 __asm__ volatile("mrs %0, ipsr\n" : "=r" (ipsr)::);
660 if (ipsr < 16) priority = 0; // could be non-zero
661 else priority = NVIC_GET_PRIORITY(ipsr - 16);
663 __asm__ volatile("mrs %0, basepri\n" : "=r" (basepri)::);
664 if (basepri > 0 && basepri < priority) priority = basepri;