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diff --git a/source/arduino/shiftout.rst b/source/arduino/shiftout.rst deleted file mode 100644 index 3815dc5..0000000 --- a/source/arduino/shiftout.rst +++ /dev/null @@ -1,136 +0,0 @@ -.. _arduino-shiftout: - -shiftOut() -========== - -Description ------------ - -Shifts out a byte of data one bit at a time. Starts from either the -most (i.e. the leftmost) or least (rightmost) significant bit. Each -bit is written in turn to a data pin, after which a clock pin is -pulsed to indicate that the bit is available. - - - -This is a software implementation; Arduino (as of 0019) also -provides an `SPI library <http://arduino.cc/en/Reference/SPI>`_ -that uses the hardware implementation. - - - -Syntax ------- - -shiftOut(dataPin, clockPin, bitOrder, value) - - - -Parameters ----------- - -dataPin: the pin on which to output each bit (*int*) - - - -clockPin: the pin to toggle once the **dataPin** has been set to -the correct value (*int*) - - - -bitOrder: which order to shift out the bits; either **MSBFIRST** or -**LSBFIRST**. -(Most Significant Bit First, or, Least Significant Bit First) - - - -value: the data to shift out. (*byte*) - - - -Returns -------- - -None - - - -Note ----- - -The **dataPin** and **clockPin** must already be configured as -outputs by a call to -`pinMode <http://arduino.cc/en/Reference/PinMode>`_\ (). - - - -**shiftOut** is currently written to output 1 byte (8 bits) so it -requires a two step operation to output values larger than 255. - -:: - - // Do this for MSBFIRST serial - int data = 500; - // shift out highbyte - shiftOut(dataPin, clock, MSBFIRST, (data >> 8)); - // shift out lowbyte - shiftOut(data, clock, MSBFIRST, data); - - // Or do this for LSBFIRST serial - data = 500; - // shift out lowbyte - shiftOut(dataPin, clock, LSBFIRST, data); - // shift out highbyte - shiftOut(dataPin, clock, LSBFIRST, (data >> 8)); - - - -Example -------- - -*For accompanying circuit, see the `tutorial on controlling a 74HC595 shift register <http://arduino.cc/en/Tutorial/ShiftOut>`_.* - - - -:: - - //**************************************************************// - // Name : shiftOutCode, Hello World // - // Author : Carlyn Maw,Tom Igoe // - // Date : 25 Oct, 2006 // - // Version : 1.0 // - // Notes : Code for using a 74HC595 Shift Register // - // : to count from 0 to 255 // - //**************************************************************** - - //Pin connected to ST_CP of 74HC595 - int latchPin = 8; - //Pin connected to SH_CP of 74HC595 - int clockPin = 12; - ////Pin connected to DS of 74HC595 - int dataPin = 11; - - void setup() { - //set pins to output because they are addressed in the main loop - pinMode(latchPin, OUTPUT); - pinMode(clockPin, OUTPUT); - pinMode(dataPin, OUTPUT); - } - - void loop() { - //count up routine - for (int j = 0; j < 256; j++) { - //ground latchPin and hold low for as long as you are transmitting - digitalWrite(latchPin, LOW); - shiftOut(dataPin, clockPin, LSBFIRST, j); - //return the latch pin high to signal chip that it - //no longer needs to listen for information - digitalWrite(latchPin, HIGH); - delay(1000); - } - } - - - - -.. include:: cc-attribution.txt
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