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-rw-r--r--source/lang/api/constants.rst8
-rw-r--r--source/lang/api/shiftout.rst99
-rw-r--r--source/lang/unimplemented/shiftout.rst136
3 files changed, 99 insertions, 144 deletions
diff --git a/source/lang/api/constants.rst b/source/lang/api/constants.rst
index 72738b8..2e968e7 100644
--- a/source/lang/api/constants.rst
+++ b/source/lang/api/constants.rst
@@ -61,14 +61,6 @@ pin is configured as an ``INPUT`` (using :ref:`pinMode()
<lang-digitalread>`, the microcontroller will report ``HIGH`` if a
voltage of 3 volts or more is present at the pin.
-.. TODO? Following seems false; check it out sometime, leave out for now:
-
-.. A pin may also be configured as an ``INPUT`` with ``pinMode()``, and
-.. subsequently made ``HIGH`` with :ref:`digitalWrite()
-.. <lang-digitalwrite>`, this will set the internal pullup resistors,
-.. which will *steer* the input pin to a HIGH reading unless it is pulled
-.. LOW by external circuitry.
-
When a pin is configured to ``OUTPUT`` with pinMode, and set to
``HIGH`` with :ref:`digitalWrite() <lang-digitalwrite>`, the pin is at
3.3 volts. In this state it can *source* current, e.g. light an LED
diff --git a/source/lang/api/shiftout.rst b/source/lang/api/shiftout.rst
new file mode 100644
index 0000000..1d9ba12
--- /dev/null
+++ b/source/lang/api/shiftout.rst
@@ -0,0 +1,99 @@
+.. highlight:: cpp
+
+.. _lang-shiftout:
+
+shiftOut()
+==========
+
+Shift out a byte of data, one bit at a time.
+
+.. contents:: Contents
+ :local:
+
+Library Documentation
+---------------------
+
+.. doxygenfunction:: shiftOut
+
+Discussion
+----------
+
+This is a software implementation. There is also a hardware :ref:`SPI
+<spi>` library available which will be faster and consume less CPU
+cycles than this function.
+
+Note that the ``dataPin`` and ``clockPin`` must already be configured
+to :ref:`OUTPUT <lang-constants-output>` mode by a call to
+:ref:`pinMode() <lang-pinmode>`.
+
+Also note that since shiftOut() outputs 1 byte (8 bits) at a time, it
+requires multiple steps to output values larger than 255.
+
+Examples
+--------
+
+To use these examples, replace ``dataPin`` and ``clockPin`` with the
+numbers of the pins you want to use::
+
+ /* MSBFIRST example */
+
+ uint16 data = 500;
+ // shift out high byte
+ shiftOut(dataPin, clockPin, MSBFIRST, (data >> 8));
+ // shift out low byte
+ shiftOut(dataPin, clockPin, MSBFIRST, data);
+
+ /* LSBFIRST serial */
+
+ data = 500;
+ // shift out low byte
+ shiftOut(dataPin, clockPin, LSBFIRST, data);
+ // shift out high byte
+ shiftOut(dataPin, clockPin, LSBFIRST, (data >> 8));
+
+Arduino Tutorial Example
+------------------------
+
+This Arduino example runs unmodified on the Maple. 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:: /lang/cc-attribution.txt
diff --git a/source/lang/unimplemented/shiftout.rst b/source/lang/unimplemented/shiftout.rst
deleted file mode 100644
index ff3852f..0000000
--- a/source/lang/unimplemented/shiftout.rst
+++ /dev/null
@@ -1,136 +0,0 @@
-.. _lang-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:: /lang/cc-attribution.txt