project additions/changes

labW9barnestr/Inc/uart_driver.h

@@ -0,0 +1,49 @@
+/*
+ * uart_driver.h
+ *
+ *  Created on: Nov 8, 2016
+ *      Author: barnekow
+ */
+
+#ifndef UART_DRIVER_H_
+#define UART_DRIVER_H_
+
+#include <inttypes.h>
+
+// RCC registers
+#define RCC_APB1ENR (volatile uint32_t*) 0x40023840
+#define RCC_AHB1ENR (volatile uint32_t*) 0x40023830
+
+#define GPIOAEN 0		// GPIOA Enable is bit 0 in RCC_APB1LPENR
+#define USART2EN 17  // USART2 enable is bit 17 in RCC_AHB1LPENR
+
+// GPIOA registers
+#define GPIOA_MODER (volatile uint32_t*) 0x40020000
+#define GPIOA_AFRL  (volatile uint32_t*) 0x40020020
+#define USART_SR    (volatile uint32_t*) 0x40004400
+#define USART_DR    (volatile uint32_t*) 0x40004404
+#define USART_BRR   (volatile uint32_t*) 0x40004408
+#define USART_CR1   (volatile uint32_t*) 0x4000440c
+#define USART_CR2   (volatile uint32_t*) 0x40004410
+#define USART_CR3   (volatile uint32_t*) 0x40004414
+
+// CR1 bits
+#define UE 13 //UART enable
+#define TE 3  // Transmitter enable
+#define RE 2  // Receiver enable
+
+// Status register bits
+#define TXE 7  // Transmit register empty
+#define RXNE 5  // Receive register is not empty..char received
+
+// Function prototypes
+extern void init_usart2(uint32_t baud, uint32_t sysclk);
+extern char usart2_getch();
+extern void usart2_putch(char c);
+
+// syscalls overrides
+int _read(int file, char *ptr, int len);
+int _write(int file, char *ptr, int len);
+
+
+#endif /* UART_DRIVER_H_ */