#define GPIO_FUNC_SEL0 0x80000018 /* GPIO 15 - 0; 2 bit blocks */ #define GPIO_FUNC_SEL1 0x8000001c /* GPIO 16 - 31; 2 bit blocks*/ #define BASE_UART1 0x80005000 #define UART1_CON 0x80005000 #define UART1_STAT 0x80005004 #define UART1_DATA 0x80005008 #define UR1CON 0x8000500c #define UT1CON 0x80005010 #define UART1_CTS 0x80005014 #define UART1_BR 0x80005018 #include "embedded_types.h" #define DELAY 100000 void main(void) { /* Restore UART regs. to default */ /* in case there is still bootloader state leftover */ *(volatile uint32_t *)UART1_CON = 0x0000c800; /* mask interrupts, 16 bit sample --- helps explain the baud rate */ /* INC = 76; MOD = 1000 */ *(volatile uint32_t *)UART1_BR = 0x004C03E8; /* Baud rate: (INC<<16 || MOD) */ /* is 115200 @ 24 MHz --- unexplained */ /* see Section 11.5.1.2 Alternate Modes */ /* you must enable the peripheral first BEFORE setting the function in GPIO_FUNC_SEL */ /* From the datasheet: "The peripheral function will control operation of the pad IF */ /* THE PERIPHERAL IS ENABLED. */ *(volatile uint32_t *)UART1_CON = 0x00000003; /* enable receive and transmit */ *(volatile uint32_t *)GPIO_FUNC_SEL0 = ( (0x01 << (14*2)) | (0x01 << (15*2)) ); /* set GPIO15-14 to UART (UART1 TX and RX)*/ uint32_t i; while(1) { for(i=0; i 0) { */ /* /\* Receive buffer isn't empty *\/ */ /* /\* read a byte and write it to the transmit buffer *\/ */ /* } */ /* }; */ }