arduino-esp32/cores/esp32/wiring_shift.c
2019-02-14 13:11:08 +01:00

52 lines
1.7 KiB
C

/*
wiring_shift.c - shiftOut() function
Part of Arduino - http://www.arduino.cc/
Copyright (c) 2005-2006 David A. Mellis
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General
Public License along with this library; if not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330,
Boston, MA 02111-1307 USA
$Id: wiring.c 248 2007-02-03 15:36:30Z mellis $
*/
#include "esp32-hal.h"
#include "wiring_private.h"
uint8_t shiftIn(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder) {
uint8_t value = 0;
uint8_t i;
for(i = 0; i < 8; ++i) {
//digitalWrite(clockPin, HIGH);
if(bitOrder == LSBFIRST)
value |= digitalRead(dataPin) << i;
else
value |= digitalRead(dataPin) << (7 - i);
digitalWrite(clockPin, HIGH);
digitalWrite(clockPin, LOW);
}
return value;
}
void shiftOut(uint8_t dataPin, uint8_t clockPin, uint8_t bitOrder, uint8_t val) {
uint8_t i;
for(i = 0; i < 8; i++) {
if(bitOrder == LSBFIRST)
digitalWrite(dataPin, !!(val & (1 << i)));
else
digitalWrite(dataPin, !!(val & (1 << (7 - i))));
digitalWrite(clockPin, HIGH);
digitalWrite(clockPin, LOW);
}
}