source: arduino-1-6-7/trunk/fuentes/arduino-ide-amd64/hardware/arduino/avr/cores/arduino/wiring_shift.c @ 4837

Last change on this file since 4837 was 4837, checked in by daduve, 2 years ago

Adding new version

File size: 1.5 KB
Line 
1/*
2  wiring_shift.c - shiftOut() function
3  Part of Arduino - http://www.arduino.cc/
4
5  Copyright (c) 2005-2006 David A. Mellis
6
7  This library is free software; you can redistribute it and/or
8  modify it under the terms of the GNU Lesser General Public
9  License as published by the Free Software Foundation; either
10  version 2.1 of the License, or (at your option) any later version.
11
12  This library is distributed in the hope that it will be useful,
13  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15  Lesser General Public License for more details.
16
17  You should have received a copy of the GNU Lesser General
18  Public License along with this library; if not, write to the
19  Free Software Foundation, Inc., 59 Temple Place, Suite 330,
20  Boston, MA  02111-1307  USA
21*/
22
23#include "wiring_private.h"
24
25uint8_t shiftIn(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder) {
26        uint8_t value = 0;
27        uint8_t i;
28
29        for (i = 0; i < 8; ++i) {
30                digitalWrite(clockPin, HIGH);
31                if (bitOrder == LSBFIRST)
32                        value |= digitalRead(dataPin) << i;
33                else
34                        value |= digitalRead(dataPin) << (7 - i);
35                digitalWrite(clockPin, LOW);
36        }
37        return value;
38}
39
40void shiftOut(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, uint8_t val)
41{
42        uint8_t i;
43
44        for (i = 0; i < 8; i++)  {
45                if (bitOrder == LSBFIRST)
46                        digitalWrite(dataPin, !!(val & (1 << i)));
47                else   
48                        digitalWrite(dataPin, !!(val & (1 << (7 - i))));
49                       
50                digitalWrite(clockPin, HIGH);
51                digitalWrite(clockPin, LOW);           
52        }
53}
Note: See TracBrowser for help on using the repository browser.