28 lines
713 B
C
28 lines
713 B
C
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#include "sysutil.h"
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#define COM1_BASE 0x3F8
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#define COM1_THR (COM1_BASE + 0)
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#define LSR_THRE 0x20
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#define COM1_LSR (COM1_BASE + 5)
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/*===========================================================================*
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* ser_putc *
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*===========================================================================*/
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void ser_putc(char c)
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{
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u32_t b;
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int i;
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int lsr, thr;
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lsr= COM1_LSR;
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thr= COM1_THR;
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for (i= 0; i<10000; i++)
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{
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if (sys_inb(lsr, &b) != OK)
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return;
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if (b & LSR_THRE)
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break;
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}
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sys_outb(thr, c);
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}
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