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Diffstat (limited to 'protocol/usb_hid/arduino-1.0.1/cores/arduino/wiring_pulse.c')
-rw-r--r--protocol/usb_hid/arduino-1.0.1/cores/arduino/wiring_pulse.c69
1 files changed, 0 insertions, 69 deletions
diff --git a/protocol/usb_hid/arduino-1.0.1/cores/arduino/wiring_pulse.c b/protocol/usb_hid/arduino-1.0.1/cores/arduino/wiring_pulse.c
deleted file mode 100644
index 0d968865d..000000000
--- a/protocol/usb_hid/arduino-1.0.1/cores/arduino/wiring_pulse.c
+++ /dev/null
@@ -1,69 +0,0 @@
-/*
- wiring_pulse.c - pulseIn() 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 "wiring_private.h"
-#include "pins_arduino.h"
-
-/* Measures the length (in microseconds) of a pulse on the pin; state is HIGH
- * or LOW, the type of pulse to measure. Works on pulses from 2-3 microseconds
- * to 3 minutes in length, but must be called at least a few dozen microseconds
- * before the start of the pulse. */
-unsigned long pulseIn(uint8_t pin, uint8_t state, unsigned long timeout)
-{
- // cache the port and bit of the pin in order to speed up the
- // pulse width measuring loop and achieve finer resolution. calling
- // digitalRead() instead yields much coarser resolution.
- uint8_t bit = digitalPinToBitMask(pin);
- uint8_t port = digitalPinToPort(pin);
- uint8_t stateMask = (state ? bit : 0);
- unsigned long width = 0; // keep initialization out of time critical area
-
- // convert the timeout from microseconds to a number of times through
- // the initial loop; it takes 16 clock cycles per iteration.
- unsigned long numloops = 0;
- unsigned long maxloops = microsecondsToClockCycles(timeout) / 16;
-
- // wait for any previous pulse to end
- while ((*portInputRegister(port) & bit) == stateMask)
- if (numloops++ == maxloops)
- return 0;
-
- // wait for the pulse to start
- while ((*portInputRegister(port) & bit) != stateMask)
- if (numloops++ == maxloops)
- return 0;
-
- // wait for the pulse to stop
- while ((*portInputRegister(port) & bit) == stateMask) {
- if (numloops++ == maxloops)
- return 0;
- width++;
- }
-
- // convert the reading to microseconds. The loop has been determined
- // to be 20 clock cycles long and have about 16 clocks between the edge
- // and the start of the loop. There will be some error introduced by
- // the interrupt handlers.
- return clockCyclesToMicroseconds(width * 21 + 16);
-}