use atmel studio's startup and linker script

1 files changed, 38 insertions, 108 deletions

diff --git a/Sensor Watch Starter Project/main.c b/Sensor Watch Starter Project/main.c
index 5c0aadec..2ced0560 100755
--- a/Sensor Watch Starter Project/main.c
+++ b/Sensor Watch Starter Project/main.c
@@ -36,139 +36,69 @@
 #include "hal_gpio.h"
 
 //-----------------------------------------------------------------------------
-#define PERIOD_FAST     100
-#define PERIOD_SLOW     500
-
 HAL_GPIO_PIN(LED,       A, 21)
-HAL_GPIO_PIN(BUTTON,    A, 30)
 HAL_GPIO_PIN(UART_TX,   B, 0)
 HAL_GPIO_PIN(UART_RX,   B, 2)
 
 //-----------------------------------------------------------------------------
-static void timer_set_period(uint16_t i)
-{
-  TC3->COUNT16.CC[0].reg = (F_CPU / 1000ul / 256) * i;
-  TC3->COUNT16.COUNT.reg = 0;
-}
+static void uart_init(uint32_t baud) {
+    uint64_t br = (uint64_t)65536 * (F_CPU - 16 * baud) / F_CPU;
 
-//-----------------------------------------------------------------------------
-void irq_handler_tc3(void)
-{
-  if (TC3->COUNT16.INTFLAG.reg & TC_INTFLAG_MC(1))
-  {
-    HAL_GPIO_LED_toggle();
-    TC3->COUNT16.INTFLAG.reg = TC_INTFLAG_MC(1);
-  }
-}
+    HAL_GPIO_UART_TX_out();
+    HAL_GPIO_UART_TX_pmuxen(HAL_GPIO_PMUX_C);
+    HAL_GPIO_UART_RX_in();
+    HAL_GPIO_UART_RX_pmuxen(HAL_GPIO_PMUX_C);
 
-//-----------------------------------------------------------------------------
-static void timer_init(void)
-{
-  MCLK->APBCMASK.reg |= MCLK_APBCMASK_TC3;
+    MCLK->APBCMASK.reg |= MCLK_APBCMASK_SERCOM3;
 
-  GCLK->PCHCTRL[TC3_GCLK_ID].reg = GCLK_PCHCTRL_GEN(0) | GCLK_PCHCTRL_CHEN;
-  while (0 == (GCLK->PCHCTRL[TC3_GCLK_ID].reg & GCLK_PCHCTRL_CHEN));
+    GCLK->PCHCTRL[SERCOM3_GCLK_ID_CORE].reg = GCLK_PCHCTRL_GEN(0) | GCLK_PCHCTRL_CHEN;
+    while (0 == (GCLK->PCHCTRL[SERCOM3_GCLK_ID_CORE].reg & GCLK_PCHCTRL_CHEN));
 
-  TC3->COUNT16.CTRLA.reg = TC_CTRLA_MODE_COUNT16 | TC_CTRLA_PRESCALER(6/*DIV256*/) |
-      TC_CTRLA_PRESCSYNC_RESYNC;
+    SERCOM3->USART.CTRLA.reg =
+        SERCOM_USART_CTRLA_DORD | SERCOM_USART_CTRLA_MODE(1/*USART_INT_CLK*/) |
+        SERCOM_USART_CTRLA_RXPO(0/*PAD0*/) | SERCOM_USART_CTRLA_TXPO(1/*PAD2*/);
 
-  TC3->COUNT16.WAVE.reg = TC_WAVE_WAVEGEN_MFRQ;
+    SERCOM3->USART.CTRLB.reg = SERCOM_USART_CTRLB_RXEN | SERCOM_USART_CTRLB_TXEN |
+        SERCOM_USART_CTRLB_CHSIZE(0/*8 bits*/);
 
-  TC3->COUNT16.COUNT.reg = 0;
+    SERCOM3->USART.BAUD.reg = (uint16_t)br;
 
-  timer_set_period(PERIOD_SLOW);
-
-  TC3->COUNT16.CTRLA.reg |= TC_CTRLA_ENABLE;
-
-  TC3->COUNT16.INTENSET.reg = TC_INTENSET_MC(1);
-  NVIC_EnableIRQ(TC3_IRQn);
+    SERCOM3->USART.CTRLA.reg |= SERCOM_USART_CTRLA_ENABLE;
 }
 
 //-----------------------------------------------------------------------------
-static void uart_init(uint32_t baud)
-{
-  uint64_t br = (uint64_t)65536 * (F_CPU - 16 * baud) / F_CPU;
-
-  HAL_GPIO_UART_TX_out();
-  HAL_GPIO_UART_TX_pmuxen(HAL_GPIO_PMUX_C);
-  HAL_GPIO_UART_RX_in();
-  HAL_GPIO_UART_RX_pmuxen(HAL_GPIO_PMUX_C);
-
-  MCLK->APBCMASK.reg |= MCLK_APBCMASK_SERCOM3;
-
-  GCLK->PCHCTRL[SERCOM3_GCLK_ID_CORE].reg = GCLK_PCHCTRL_GEN(0) | GCLK_PCHCTRL_CHEN;
-  while (0 == (GCLK->PCHCTRL[SERCOM3_GCLK_ID_CORE].reg & GCLK_PCHCTRL_CHEN));
-
-  SERCOM3->USART.CTRLA.reg =
-      SERCOM_USART_CTRLA_DORD | SERCOM_USART_CTRLA_MODE(1/*USART_INT_CLK*/) |
-      SERCOM_USART_CTRLA_RXPO(0/*PAD0*/) | SERCOM_USART_CTRLA_TXPO(1/*PAD2*/);
-
-  SERCOM3->USART.CTRLB.reg = SERCOM_USART_CTRLB_RXEN | SERCOM_USART_CTRLB_TXEN |
-      SERCOM_USART_CTRLB_CHSIZE(0/*8 bits*/);
-
-  SERCOM3->USART.BAUD.reg = (uint16_t)br;
-
-  SERCOM3->USART.CTRLA.reg |= SERCOM_USART_CTRLA_ENABLE;
+static void uart_putc(char c) {
+    while (!(SERCOM3->USART.INTFLAG.reg & SERCOM_USART_INTFLAG_DRE));
+    SERCOM3->USART.DATA.reg = c;
 }
 
 //-----------------------------------------------------------------------------
-static void uart_putc(char c)
-{
-  while (!(SERCOM3->USART.INTFLAG.reg & SERCOM_USART_INTFLAG_DRE));
-  SERCOM3->USART.DATA.reg = c;
+static void uart_puts(char *s) {
+    while (*s) uart_putc(*s++);
 }
 
 //-----------------------------------------------------------------------------
-static void uart_puts(char *s)
-{
-  while (*s)
-    uart_putc(*s++);
+static void sys_init(void) {
+    // Switch to 16MHz clock (disable prescaler)
+    OSCCTRL->OSC16MCTRL.reg = OSCCTRL_OSC16MCTRL_ENABLE | OSCCTRL_OSC16MCTRL_FSEL_16;
+    // Switch to the highest performance level
+    PM->INTFLAG.reg = PM_INTFLAG_PLRDY;
+    PM->PLCFG.reg = PM_PLCFG_PLSEL_PL2_Val;
+    while (!PM->INTFLAG.reg);
 }
 
 //-----------------------------------------------------------------------------
-static void sys_init(void)
-{
-  // Switch to 16MHz clock (disable prescaler)
-  OSCCTRL->OSC16MCTRL.reg = OSCCTRL_OSC16MCTRL_ENABLE | OSCCTRL_OSC16MCTRL_FSEL_16;
-
-  // Switch to the highest performance level
-  PM->INTFLAG.reg = PM_INTFLAG_PLRDY;
-  PM->PLCFG.reg = PM_PLCFG_PLSEL_PL2_Val;
-  while (!PM->INTFLAG.reg);
-}
+int main(void) {
+    sys_init();
+    uart_init(115200);
+    HAL_GPIO_LED_out();
+    HAL_GPIO_LED_set();
 
-//-----------------------------------------------------------------------------
-int main(void)
-{
-  uint32_t cnt = 0;
-  bool fast = false;
-
-  sys_init();
-  timer_init();
-  uart_init(115200);
-
-  uart_puts("\r\nHello, world!\r\n");
-
-  HAL_GPIO_LED_out();
-  HAL_GPIO_LED_clr();
-
-  HAL_GPIO_BUTTON_in();
-  HAL_GPIO_BUTTON_pullup();
-
-  while (1)
-  {
-    if (HAL_GPIO_BUTTON_read())
-      cnt = 0;
-    else if (cnt < 5001)
-      cnt++;
-
-    if (5000 == cnt)
-    {
-      fast = !fast;
-      timer_set_period(fast ? PERIOD_FAST : PERIOD_SLOW);
-      uart_putc('.');
+    uart_puts("\r\nHello, world!\r\n");
+
+    while (1) {
+        uart_putc('.');
     }
-  }
 
-  return 0;
+    return 0;
 }