PortOut.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_PORTOUT_H
00017 #define MBED_PORTOUT_H
00018 
00019 #include "platform.h"
00020 
00021 #if DEVICE_PORTOUT
00022 
00023 #include "port_api.h"
00024 #include "critical.h"
00025 
00026 namespace mbed {
00027 /** A multiple pin digital out
00028  *
00029  * @Note Synchronization level: Interrupt safe
00030  *
00031  * Example:
00032  * @code
00033  * // Toggle all four LEDs
00034  *
00035  * #include "mbed.h"
00036  *
00037  * // LED1 = P1.18  LED2 = P1.20  LED3 = P1.21  LED4 = P1.23
00038  * #define LED_MASK 0x00B40000
00039  *
00040  * PortOut ledport(Port1, LED_MASK);
00041  *
00042  * int main() {
00043  *     while(1) {
00044  *         ledport = LED_MASK;
00045  *         wait(1);
00046  *         ledport = 0;
00047  *         wait(1);
00048  *     }
00049  * }
00050  * @endcode
00051  */
00052 class PortOut {
00053 public:
00054 
00055     /** Create an PortOut, connected to the specified port
00056      *
00057      *  @param port Port to connect to (Port0-Port5)
00058      *  @param mask A bitmask to identify which bits in the port should be included (0 - ignore)
00059      */
00060     PortOut(PortName port, int mask = 0xFFFFFFFF) {
00061         core_util_critical_section_enter();
00062         port_init(&_port, port, mask, PIN_OUTPUT);
00063         core_util_critical_section_exit();
00064     }
00065 
00066     /** Write the value to the output port
00067      *
00068      *  @param value An integer specifying a bit to write for every corresponding PortOut pin
00069      */
00070     void write(int value) {
00071         port_write(&_port, value);
00072     }
00073 
00074     /** Read the value currently output on the port
00075      *
00076      *  @returns
00077      *    An integer with each bit corresponding to associated PortOut pin setting
00078      */
00079     int read() {
00080         return port_read(&_port);
00081     }
00082 
00083     /** A shorthand for write()
00084      */
00085     PortOut& operator= (int value) {
00086         write(value);
00087         return *this;
00088     }
00089 
00090     PortOut& operator= (PortOut& rhs) {
00091         write(rhs.read());
00092         return *this;
00093     }
00094 
00095     /** A shorthand for read()
00096      */
00097     operator int() {
00098         return read();
00099     }
00100 
00101 private:
00102     port_t _port;
00103 };
00104 
00105 } // namespace mbed
00106 
00107 #endif
00108 
00109 #endif