79 lines
2.2 KiB
C
79 lines
2.2 KiB
C
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/*
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* leds.c -- control the led's on a Motorola mc68ec0x0 board.
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*
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* Copyright (c) 1995 Cygnus Support
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*
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* The authors hereby grant permission to use, copy, modify, distribute,
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* and license this software and its documentation for any purpose, provided
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* that existing copyright notices are retained in all copies and that this
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* notice is included verbatim in any distributions. No written agreement,
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* license, or royalty fee is required for any of the authorized uses.
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* Modifications to this software may be copyrighted by their authors
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* and need not follow the licensing terms described here, provided that
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* the new terms are clearly indicated on the first page of each file where
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* they apply.
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*/
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#include "leds.h"
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/*
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* led_putnum -- print a hex number on the LED. the value of num must be a char with
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* the ascii value. ie... number 0 is '0', a is 'a', ' ' (null) clears
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* the led display.
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* Setting the bit to 0 turns it on, 1 turns it off.
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* the LED's are controlled by setting the right bit mask in the base
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* address.
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* The bits are:
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* [d.p | g | f | e | d | c | b | a ] is the byte.
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*
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* The locations are:
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*
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* a
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* -----
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* f | | b
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* | g |
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* -----
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* | |
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* e | | c
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* -----
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* d . d.p (decimal point)
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*/
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void
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led_putnum ( num )
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char num;
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{
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static unsigned char *leds = (unsigned char *)LED_ADDR;
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static unsigned char num_bits [18] = {
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0xff, /* clear all */
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0xc0, 0xf9, 0xa4, 0xb0, 0x99, 0x92, 0x82, 0xf8, 0x80, 0x98, /* numbers 0-9 */
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0x98, 0x20, 0x3, 0x27, 0x21, 0x4, 0xe /* letters a-f */
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};
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if (num >= '0' && num <= '9')
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num = (num - '0') + 1;
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if (num >= 'a' && num <= 'f')
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num = (num - 'a') + 12;
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if (num == ' ')
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num = 0;
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*leds = num_bits[num];
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}
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/*
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* zylons -- draw a rotating pattern. NOTE: this function never returns.
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*/
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void
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zylons()
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{
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unsigned char *leds = (unsigned char *)LED_ADDR;
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unsigned char curled = 0xfe;
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while (1)
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{
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*leds = curled;
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curled = (curled >> 1) | (curled << 7);
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delay ( 200 );
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}
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}
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