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