mirror of
git://projects.qi-hardware.com/f32xbase.git
synced 2024-07-05 06:18:35 +03:00
126 lines
2.1 KiB
C
126 lines
2.1 KiB
C
/*
|
|
* common/uart.c - UART initialization and debug output
|
|
*
|
|
* Written 2008, 2009 by Werner Almesberger
|
|
* Copyright 2008, 2009 Werner Almesberger
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*/
|
|
|
|
|
|
#include <stdarg.h>
|
|
#include <stdio.h>
|
|
|
|
#include "regs.h"
|
|
#include "uart.h"
|
|
|
|
|
|
/* gpio j4=0 */
|
|
|
|
|
|
#ifndef CONFIG_USB_PUTCHAR
|
|
|
|
void putchar(char c)
|
|
{
|
|
if (c == '\n')
|
|
putchar('\r');
|
|
SBUF0 = c;
|
|
while (!TI0);
|
|
TI0 = 0;
|
|
}
|
|
|
|
#endif /* !CONFIG_USB_PUTCHAR */
|
|
|
|
|
|
/* for now, we always use printf_tiny, which doesn't have a vprintf* version */
|
|
#ifdef noCONFIG_PRINTK
|
|
|
|
void printk(const char *fmt, ...)
|
|
{
|
|
va_list ap;
|
|
__bit saved;
|
|
|
|
va_start(ap, fmt);
|
|
saved = EA;
|
|
EA = 0;
|
|
vprintf(fmt, ap);
|
|
EA = saved;
|
|
va_end(ap);
|
|
}
|
|
|
|
#endif /* CONFIG_PRINTK */
|
|
|
|
|
|
void uart_init(uint8_t brg_mhz)
|
|
{
|
|
/*
|
|
* UART: Enable only transmitter, no interrupts.
|
|
*/
|
|
SCON0 = 0; /* also clears TI0 */
|
|
SMOD0 = S0DL1 | S0DL0;
|
|
|
|
/*
|
|
* Configure the UART to 115200bps, see table 13.1
|
|
*
|
|
* We can's support 1.5MHz (that is, without using the USB clock, but
|
|
* why would one want to run the core at 1.5MHz when USB is around ?)
|
|
*
|
|
* The closes settings would be:
|
|
*
|
|
* SBRL0 = 0xfff9; -- 107142.9 bps, error = -7%
|
|
* SBRL0 = 0xfffa; -- 125000 bps, error = +8.5%
|
|
*
|
|
* Depending on signal quality, we would need something like +/-5%.
|
|
*/
|
|
|
|
#if defined(UART_115200_BPS)
|
|
switch (brg_mhz) {
|
|
case 3:
|
|
SBRL0 = 0xfff3;
|
|
break;
|
|
case 6:
|
|
SBRL0 = 0xffe6;
|
|
break;
|
|
case 12:
|
|
SBRL0 = 0xffcc;
|
|
break;
|
|
case 24:
|
|
SBRL0 = 0xff98;
|
|
break;
|
|
case 48:
|
|
SBRL0 = 0xff30;
|
|
break;
|
|
}
|
|
#elif defined(UART_57600_BPS)
|
|
switch (brg_mhz) {
|
|
case 3:
|
|
SBRL0 = 0xffe6;
|
|
break;
|
|
case 6:
|
|
SBRL0 = 0xffcc;
|
|
break;
|
|
case 12:
|
|
SBRL0 = 0xff98;
|
|
break;
|
|
case 24:
|
|
SBRL0 = 0xff30;
|
|
break;
|
|
case 48:
|
|
SBRL0 = 0xfe5f;
|
|
break;
|
|
}
|
|
#else
|
|
#error "must set either UART_115200_BPS or UART_57600_BPS"
|
|
#endif
|
|
|
|
SBCON0 = SB0RUN | SB0PS0 | SB0PS1;
|
|
|
|
/*
|
|
* Make TX a push-pull output
|
|
*/
|
|
P0MDOUT |= 1 << 4;
|
|
}
|