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/* * leds.h -- control the led's on a Motorola mc68ec0x0 board. */ #ifndef __LEDS_H__ #define __LEDS_H__ #define LED_ADDR 0xd00003 #define LED_0 ~0x1 #define LED_1 ~0x2 #define LED_2 ~0x4 #define LED_3 ~0x8 #define LED_4 ~0x10 #define LED_5 ~0x20 #define LED_6 ~0x40 #define LED_7 ~0x80 #define LEDS_OFF 0xff #define LEDS_ON 0x0 #define FUDGE(x) ((x >= 0xa && x <= 0xf) ? (x + 'a') & 0x7f : (x + '0') & 0x7f) extern void led_putnum( char ); #endif /* __LEDS_H__ */ /* * leds.c -- control the led's on a Motorola mc68ec0x0 (IDP)board. */ #include "leds.h" void zylons(); void led_putnum(); /* * 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[num]; } /* * 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 ( 200 ); } }
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