BusOut.cpp

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 #include "drivers/BusOut.h"
00017 #include "platform/mbed_assert.h"
00018  
00019 namespace mbed {
00020  
00021 BusOut::BusOut(PinName p0, PinName p1, PinName p2, PinName p3, PinName p4, PinName p5, PinName p6, PinName p7, PinName p8, PinName p9, PinName p10, PinName p11, PinName p12, PinName p13, PinName p14, PinName p15) {
00022     PinName pins[16] = {p0, p1, p2, p3, p4, p5, p6, p7, p8, p9, p10, p11, p12, p13, p14, p15};
00023  
00024     // No lock needed in the constructor
00025     _nc_mask = 0;
00026     for (int i=0; i<16; i++) {
00027         _pin[i] = (pins[i] != NC) ? new DigitalOut(pins[i]) : 0;
00028         if (pins[i] != NC) {
00029             _nc_mask |= (1 << i);
00030         }
00031     }
00032 }
00033  
00034 BusOut::BusOut(PinName pins[16]) {
00035     // No lock needed in the constructor
00036     _nc_mask = 0;
00037     for (int i=0; i<16; i++) {
00038         _pin[i] = (pins[i] != NC) ? new DigitalOut(pins[i]) : 0;
00039         if (pins[i] != NC) {
00040             _nc_mask |= (1 << i);
00041         }
00042     }
00043 }
00044  
00045 BusOut::~BusOut() {
00046     // No lock needed in the destructor
00047     for (int i=0; i<16; i++) {
00048         if (_pin[i] != 0) {
00049             delete _pin[i];
00050         }
00051     }
00052 }
00053  
00054 void BusOut::write(int value) {
00055     lock();
00056     for (int i=0; i<16; i++) {
00057         if (_pin[i] != 0) {
00058             _pin[i]->write((value >> i) & 1);
00059         }
00060     }
00061     unlock();
00062 }
00063  
00064 int BusOut::read() {
00065     lock();
00066     int v = 0;
00067     for (int i=0; i<16; i++) {
00068         if (_pin[i] != 0) {
00069             v |= _pin[i]->read() << i;
00070         }
00071     }
00072     unlock();
00073     return v;
00074 }
00075  
00076 BusOut& BusOut::operator= (int v) {
00077     // Underlying write is thread safe
00078     write(v);
00079     return *this;
00080 }
00081  
00082 BusOut& BusOut::operator= (BusOut& rhs) {
00083     // Underlying write is thread safe
00084     write(rhs.read());
00085     return *this;
00086 }
00087  
00088 DigitalOut& BusOut::operator[] (int index) {
00089     // No lock needed since _pin is not modified outside the constructor
00090     MBED_ASSERT(index >= 0 && index <= 16);
00091     MBED_ASSERT(_pin[index]);
00092     return *_pin[index];
00093 }
00094  
00095 BusOut::operator int() {
00096     // Underlying read is thread safe
00097     return read();
00098 }
00099  
00100 void BusOut::lock() {
00101     _mutex.lock();
00102 }
00103  
00104 void BusOut::unlock() {
00105     _mutex.unlock();
00106 }
00107  
00108 } // namespace mbed