1 /*
2 * leds.c -- control the led's on a Motorola mc68ec0x0 board.
3 *
4 * Copyright (c) 1995 Cygnus Support
5 *
6 * The authors hereby grant permission to use, copy, modify, distribute,
7 * and license this software and its documentation for any purpose, provided
8 * that existing copyright notices are retained in all copies and that this
9 * notice is included verbatim in any distributions. No written agreement,
10 * license, or royalty fee is required for any of the authorized uses.
11 * Modifications to this software may be copyrighted by their authors
12 * and need not follow the licensing terms described here, provided that
13 * the new terms are clearly indicated on the first page of each file where
14 * they apply.
15 */
16 #include "leds.h"
17
18 /*
19 * led_putnum -- print a hex number on the LED. the value of num must be a char with
20 * the ascii value. ie... number 0 is '0', a is 'a', ' ' (null) clears
21 * the led display.
22 * Setting the bit to 0 turns it on, 1 turns it off.
23 * the LED's are controlled by setting the right bit mask in the base
24 * address.
25 * The bits are:
26 * [d.p | g | f | e | d | c | b | a ] is the byte.
27 *
28 * The locations are:
29 *
30 * a
31 * -----
32 * f | | b
33 * | g |
34 * -----
35 * | |
36 * e | | c
37 * -----
38 * d . d.p (decimal point)
39 */
40 void
led_putnum(num)41 led_putnum ( num )
42 char num;
43 {
44 static unsigned char *leds = (unsigned char *)LED_ADDR;
45 static unsigned char num_bits [18] = {
46 0xff, /* clear all */
47 0xc0, 0xf9, 0xa4, 0xb0, 0x99, 0x92, 0x82, 0xf8, 0x80, 0x98, /* numbers 0-9 */
48 0x98, 0x20, 0x3, 0x27, 0x21, 0x4, 0xe /* letters a-f */
49 };
50
51 if (num >= '0' && num <= '9')
52 num = (num - '0') + 1;
53
54 if (num >= 'a' && num <= 'f')
55 num = (num - 'a') + 12;
56
57 if (num == ' ')
58 num = 0;
59
60 *leds = num_bits[num];
61 }
62
63 /*
64 * zylons -- draw a rotating pattern. NOTE: this function never returns.
65 */
66 void
zylons()67 zylons()
68 {
69 unsigned char *leds = (unsigned char *)LED_ADDR;
70 unsigned char curled = 0xfe;
71
72 while (1)
73 {
74 *leds = curled;
75 curled = (curled >> 1) | (curled << 7);
76 delay ( 200 );
77 }
78 }
79