- #include <stdio.h>
- #include "NuMicro.h"
- void SYS_Init(void)
- {
- /* Set PF multi-function pins for XT1_OUT(PF.2) and XT1_IN(PF.3) */
- SYS->GPF_MFPL = (SYS->GPF_MFPL & (~SYS_GPF_MFPL_PF2MFP_Msk)) | SYS_GPF_MFPL_PF2MFP_XT1_OUT;
- SYS->GPF_MFPL = (SYS->GPF_MFPL & (~SYS_GPF_MFPL_PF3MFP_Msk)) | SYS_GPF_MFPL_PF3MFP_XT1_IN;
- /*---------------------------------------------------------------------------------------------------------*/
- /* Init System Clock */
- /*---------------------------------------------------------------------------------------------------------*/
- /* Enable HIRC clock */
- CLK_EnableXtalRC(CLK_PWRCTL_HIRCEN_Msk);
- /* Wait for HIRC clock ready */
- CLK_WaitClockReady(CLK_STATUS_HIRCSTB_Msk);
- /* Select HCLK clock source as HIRC and HCLK clock divider as 1 */
- CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_HIRC, CLK_CLKDIV0_HCLK(1));
- /* Enable HXT clock */
- CLK_EnableXtalRC(CLK_PWRCTL_HXTEN_Msk);
- /* Wait for HXT clock ready */
- CLK_WaitClockReady(CLK_STATUS_HXTSTB_Msk);
- /* Enable PLL */
- CLK->PLLCTL = CLK_PLLCTL_128MHz_HIRC;
- /* Waiting for PLL stable */
- CLK_WaitClockReady(CLK_STATUS_PLLSTB_Msk);
- /* Select HCLK clock source as PLL and HCLK source divider as 2 */
- CLK_SetHCLK(CLK_CLKSEL0_HCLKSEL_PLL, CLK_CLKDIV0_HCLK(2));
- /* Enable UART module clock */
- CLK_EnableModuleClock(UART0_MODULE);
- /* Select UART module clock source as HIRC and UART module clock divider as 1 */
- CLK_SetModuleClock(UART0_MODULE, CLK_CLKSEL1_UART0SEL_HIRC, CLK_CLKDIV0_UART0(1));
- /*---------------------------------------------------------------------------------------------------------*/
- /* Init I/O Multi-function */
- /*---------------------------------------------------------------------------------------------------------*/
- /* Set multi-function pins for UART0 RXD and TXD */
- SYS->GPB_MFPH = (SYS->GPB_MFPH & (~(UART0_RXD_PB12_Msk | UART0_TXD_PB13_Msk))) | UART0_RXD_PB12 | UART0_TXD_PB13;
- }
- void UART0_Init(void)
- {
- /*---------------------------------------------------------------------------------------------------------*/
- /* Init UART */
- /*---------------------------------------------------------------------------------------------------------*/
- /* Reset UART0 */
- SYS_ResetModule(UART0_RST);
- /* Configure UART0 and set UART0 baud rate */
- UART_Open(UART0, 115200);
- }
- void blink1(void)
- {
- static int i=0;
- i++;
- CLK_SysTickDelay(1000000);
- printf("%d\n",i);
- }
- void blink2(void)
- {
- CLK_SysTickDelay(500000);
- GPIO_TOGGLE(PB10);
- }
- void blink3(void)
- {
- CLK_SysTickDelay(100000);
- GPIO_TOGGLE(PB10);
- }
- /*---------------------------------------------------------------------------------------------------------*/
- /* Main Function */
- /*---------------------------------------------------------------------------------------------------------*/
- int32_t main(void)
- {
- void (*blink)(void);
- blink=blink1;
- /* Unlock protected registers */
- SYS_UnlockReg();
- /* Init System, peripheral clock and multi-function I/O */
- SYS_Init();
- /* Lock protected registers */
- SYS_LockReg();
- /* Init UART0 for printf */
- UART0_Init();
- printf("\n\nCPU [url=home.php?mod=space&uid=72445]@[/url] %dHz\n", SystemCoreClock);
- printf("+-------------------------------------------------+\n");
- printf("| PB.10(Output) and PG.4(Input) Sample Code |\n");
- printf("+-------------------------------------------------+\n\n");
- /*-----------------------------------------------------------------------------------------------------*/
- /* GPIO Basic Mode Test --- Use Pin Data Input/Output to control GPIO pin */
- /*-----------------------------------------------------------------------------------------------------*/
- printf(" >> LED at PB.10 ; Button1 at PG.4 \n");
- /* Configure PB.10 as Output mode and PG.4 as Input mode then close it */
- GPIO_SetMode(PB, BIT10, GPIO_MODE_OUTPUT);
- GPIO_SetMode(PG, BIT4, GPIO_MODE_INPUT);
- PB10 = 1;
- printf("GPIO PB.10(output mode) and PD.7(input mode) ......");
-
-
- while(1)
- {
- blink();
-
- if(PG4==0)
- {
- CLK_SysTickDelay(50);
- while(PG4==0){}
- {
- if (blink==blink1) blink=blink2;
- else if(blink==blink2) blink=blink3;
- else if(blink==blink3) blink=blink1;
-
- }
- }
- }
- }
初始化的时候我让blink指向了blink1,但是如果我删除blink1中的内容,那么按键操作后发现无法切换回什么都不做的blink1,如果我给blink1填充一些内容,比如上面代码中打印一些编号。
就可以切换回来,好奇怪啊。
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