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/*
* leds.c -- control the led's on a Motorola mc68ec0x0 board.
* Written by rob@cygnus.com (Rob Savoye)
*/
#include "leds.h"
void zylons();
void led_putnum();
void clear_leds();
/*
* led_putnum -- print a hex number on the LED. the value of num must be a char with
* the ascii value. ie... number 0 is '0', a is 'a', ' ' (null) clears
* the led display.
* Setting the bit to 0 turns it on, 1 turns it off.
* the LED's are controlled by setting the right bit mask in the base
* address.
* The bits are:
* [d.p | g | f | e | d | c | b | a ] is the byte.
*
* The locations are:
*
* a
* -----
* f | | b
* | g |
* -----
* | |
* e | | c
* -----
* d . d.p (decimal point)
*/
void
led_putnum ( num )
char num;
{
static unsigned char *leds = (unsigned char *)LED_ADDR;
static unsigned char num_bits [18] = {
0xff, /* clear all */
0xc0, 0xf9, 0xa4, 0xb0, 0x99, 0x92, 0x82, 0xf8, 0x80, 0x98, /* numbers 0-9 */
0x98, 0x20, 0x3, 0x27, 0x21, 0x4, 0xe /* letters a-f */
};
if (num >= '0' && num <= '9')
num = (num - '0') + 1;
if (num >= 'a' && num <= 'f')
num = (num - 'a') + 12;
if (num == ' ')
num = 0;
*leds = num_bits[(int)num];
}
/* This procedure added by Doug McBride, Colorado Space Grant College --
Probably should be a macro instead */
void
clear_leds ( )
{
static unsigned char *leds = (unsigned char *)LED_ADDR;
*leds = 0xFF;
}
/*
* zylons -- draw a rotating pattern. NOTE: this function never returns.
*/
void
zylons()
{
unsigned char *leds = (unsigned char *)LED_ADDR;
unsigned char curled = 0xfe;
while (1)
{
*leds = curled;
curled = (curled >> 1) | (curled << 7);
delay ( 8000 );
}
}
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