mirror of
https://github.com/rfivet/stm32bringup.git
synced 2024-11-16 09:36:01 -05:00
57 lines
1.5 KiB
C
57 lines
1.5 KiB
C
|
/* board.c -- board mapping abstraction
|
||
|
** Copyright (c) 2020 Renaud Fivet
|
||
|
*/
|
||
|
|
||
|
#define SYSTICK ((volatile long *) 0xE000E010)
|
||
|
#define SYSTICK_CSR SYSTICK[ 0]
|
||
|
#define SYSTICK_RVR SYSTICK[ 1]
|
||
|
#define SYSTICK_CVR SYSTICK[ 2]
|
||
|
|
||
|
#define CAT( a, b) a##b
|
||
|
#define HEXA( a) CAT( 0x, a)
|
||
|
#define RCC ((volatile long *) 0x40021000)
|
||
|
#define RCC_AHBENR RCC[ 5]
|
||
|
#define RCC_AHBENR_IOP( h) (1 << (17 + HEXA( h) - 0xA))
|
||
|
|
||
|
#define GPIOA ((volatile long *) 0x48000000)
|
||
|
#define GPIOB ((volatile long *) 0x48000400)
|
||
|
#define GPIO( x) CAT( GPIO, x)
|
||
|
#define MODER 0
|
||
|
#define ODR 5
|
||
|
|
||
|
/* user LED ON when PA4 is high */
|
||
|
#define LED_IOP A
|
||
|
#define LED_PIN 4
|
||
|
#define LED_ON 1
|
||
|
|
||
|
void SysTick_Handler( void) {
|
||
|
#ifdef LED_ON
|
||
|
GPIO( LED_IOP)[ ODR] ^= 1 << LED_PIN ; /* Toggle User LED */
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
int init( void) {
|
||
|
/* By default SYSCLK == HSI [8MHZ] */
|
||
|
|
||
|
/* SYSTICK */
|
||
|
SYSTICK_RVR = 1000000 - 1 ; /* HBA / 8 */
|
||
|
SYSTICK_CVR = 0 ;
|
||
|
SYSTICK_CSR = 3 ; /* HBA / 8, Interrupt ON, Enable */
|
||
|
/* SysTick_Handler will execute every 1s from now on */
|
||
|
|
||
|
#ifdef LED_ON
|
||
|
/* User LED ON */
|
||
|
RCC_AHBENR |= RCC_AHBENR_IOP( LED_IOP) ; /* Enable IOPx periph */
|
||
|
GPIO( LED_IOP)[ MODER] |= 1 << (LED_PIN * 2) ; /* LED_IO Output [01],
|
||
|
** over default 00 */
|
||
|
/* OTYPER Push-Pull by default */
|
||
|
/* Pxn output default LOW at reset */
|
||
|
# if LED_ON
|
||
|
SysTick_Handler() ;
|
||
|
# endif
|
||
|
#endif
|
||
|
return 0 ;
|
||
|
}
|
||
|
|
||
|
/* end of board.c */
|