PortIn.h

00001 /* mbed Microcontroller Library
00002  * Copyright (c) 2006-2013 ARM Limited
00003  *
00004  * Licensed under the Apache License, Version 2.0 (the "License");
00005  * you may not use this file except in compliance with the License.
00006  * You may obtain a copy of the License at
00007  *
00008  *     http://www.apache.org/licenses/LICENSE-2.0
00009  *
00010  * Unless required by applicable law or agreed to in writing, software
00011  * distributed under the License is distributed on an "AS IS" BASIS,
00012  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00013  * See the License for the specific language governing permissions and
00014  * limitations under the License.
00015  */
00016 #ifndef MBED_PORTIN_H
00017 #define MBED_PORTIN_H
00018 
00019 #include "platform.h"
00020 
00021 #if DEVICE_PORTIN
00022 
00023 #include "port_api.h"
00024 
00025 namespace mbed {
00026 
00027 /** A multiple pin digital input
00028  *
00029  *  Example:
00030  * @code
00031  * // Switch on an LED if any of mbed pins 21-26 is high
00032  *
00033  * #include "mbed.h"
00034  *
00035  * PortIn     p(Port2, 0x0000003F);   // p21-p26
00036  * DigitalOut ind(LED4);
00037  *
00038  * int main() {
00039  *     while(1) {
00040  *         int pins = p.read();
00041  *         if(pins) {
00042  *             ind = 1;
00043  *         } else {
00044  *             ind = 0;
00045  *         }
00046  *     }
00047  * }
00048  * @endcode
00049  */
00050 class PortIn {
00051 public:
00052 
00053     /** Create an PortIn, connected to the specified port
00054      *
00055      *  @param port Port to connect to (Port0-Port5)
00056      *  @param mask A bitmask to identify which bits in the port should be included (0 - ignore)
00057         */
00058     PortIn(PortName port, int mask = 0xFFFFFFFF) {
00059         port_init(&_port, port, mask, PIN_INPUT);
00060     }
00061 
00062     /** Read the value currently output on the port
00063      *
00064      *  @returns
00065      *    An integer with each bit corresponding to associated port pin setting
00066      */
00067     int read() {
00068         return port_read(&_port);
00069     }
00070 
00071     /** Set the input pin mode
00072      *
00073      *  @param mode PullUp, PullDown, PullNone, OpenDrain
00074      */
00075     void mode(PinMode mode) {
00076         port_mode(&_port, mode);
00077     }
00078 
00079     /** A shorthand for read()
00080      */
00081     operator int() {
00082         return read();
00083     }
00084 
00085 private:
00086     port_t _port;
00087 };
00088 
00089 } // namespace mbed
00090 
00091 #endif
00092 
00093 #endif