67 lines
1.3 KiB
C
67 lines
1.3 KiB
C
/*
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* Copyright (c) 2006-2021, RT-Thread Development Team
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*
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* SPDX-License-Identifier: Apache-2.0
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*
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* Change Logs:
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* Date Author Notes
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* 2006-09-15 QiuYi the first version
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* 2006-10-10 Bernard use keyboard instead of serial
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*/
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#include <rtthread.h>
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#include <rthw.h>
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#include <bsp.h>
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/**
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* @addtogroup QEMU
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*/
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/*@{*/
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/**
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* This function initializes serial
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*/
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void rt_serial_init(void)
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{
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outb(COM1+3,0x80); /* set DLAB of line control reg */
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outb(COM1,0x0c); /* LS of divisor (48 -> 2400 bps */
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outb(COM1+1,0x00); /* MS of divisor */
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outb(COM1+3,0x03); /* reset DLAB */
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outb(COM1+4,0x0b); /* set DTR,RTS, OUT_2 */
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outb(COM1+1,0x0d); /* enable all intrs but writes */
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inb(COM1); /* read data port to reset things (?) */
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}
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/**
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* This function read a character from serial without interrupt enable mode
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*
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* @return the read char
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*/
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char rt_serial_getc(void)
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{
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while(!(inb(COM1+COMSTATUS) & COMDATA));
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return inb(COM1+COMREAD);
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}
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/**
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* This function will write a character to serial without interrupt enable mode
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*
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* @param c the char to write
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*/
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void rt_serial_putc(const char c)
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{
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int val;
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while(1)
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{
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if ((val = inb(COM1+COMSTATUS)) & THRE)
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break;
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}
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outb(COM1+COMWRITE, c&0xff);
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}
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/*@}*/
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