this works, but there are unexplained things like why it can't print

the whole message, why I can't enable RX, and why the baud number is
what it is.
This commit is contained in:
Mariano Alvira 2009-03-30 14:07:42 -04:00
parent b77fb10e63
commit 09e99ba429

57
tests/uart1-loopback.c Normal file
View File

@ -0,0 +1,57 @@
#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 1000
void main(void) {
volatile uint32_t i;
*(volatile uint32_t *)GPIO_FUNC_SEL0 = (0x01 << (14*2)); /* set GPIO14 to UART (UART1 TX)*/
// *(volatile uint32_t *)GPIO_FUNC_SEL0 = ( (0x01 << (14*2)) || (0x01 << (15*2)) ); /* set GPIO15-14 to UART (UART1 TX and RX)*/
*(volatile uint32_t *)UART1_BR = 0x004C03E8; /* Baud rate: (INC<<16 || MOD) */ /* is 115200 @ 24 MHz --- unexplained */
*(volatile uint32_t *)UART1_CON = 0x00000003; /* enable receive and transmit */
while(1) {
for(i=0; i<DELAY; i++) { continue; }
*(volatile uint32_t *)UART1_DATA = 'H';
/* for(i=0; i<DELAY; i++) { continue; }
*(volatile uint32_t *)UART1_DATA = 'e';
for(i=0; i<DELAY; i++) { continue; }
*(volatile uint32_t *)UART1_DATA = 'l';
for(i=0; i<DELAY; i++) { continue; }
*(volatile uint32_t *)UART1_DATA = 'l';
for(i=0; i<DELAY; i++) { continue; }
*(volatile uint32_t *)UART1_DATA = 'o';
for(i=0; i<DELAY; i++) { continue; }
*(volatile uint32_t *)UART1_DATA = ' ';
*(volatile uint32_t *)UART1_DATA = 'W';
*(volatile uint32_t *)UART1_DATA = 'o';
*(volatile uint32_t *)UART1_DATA = 'r';
*(volatile uint32_t *)UART1_DATA = 'l';
*(volatile uint32_t *)UART1_DATA = 'd';
*(volatile uint32_t *)UART1_DATA = '\n';
*(volatile uint32_t *)UART1_DATA = '\r';*/
}
/* while(1) { */
/* if(*(volatile uint32_t*)UR1CON > 0) { */
/* /\* Receive buffer isn't empty *\/ */
/* /\* read a byte and write it to the transmit buffer *\/ */
/* } */
/* }; */
}