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AnalogOut.h@64:75c1708b266b, 2013-07-05 (annotated)

Committer:
ldyz
Date:
Fri Jul 05 13:16:13 2013 +0000
Revision:
64:75c1708b266b
Parent:
59:0883845fe643 
test

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 44:24d45a770a51 1 /* mbed Microcontroller Library
emilmont 54:71b101360fb9 2 * Copyright (c) 2006-2013 ARM Limited
emilmont 44:24d45a770a51 3 *
emilmont 59:0883845fe643 4 * Licensed under the Apache License, Version 2.0 (the "License");
emilmont 59:0883845fe643 5 * you may not use this file except in compliance with the License.
emilmont 59:0883845fe643 6 * You may obtain a copy of the License at
emilmont 59:0883845fe643 7 *
emilmont 59:0883845fe643 8 * http://www.apache.org/licenses/LICENSE-2.0
emilmont 44:24d45a770a51 9 *
emilmont 59:0883845fe643 10 * Unless required by applicable law or agreed to in writing, software
emilmont 59:0883845fe643 11 * distributed under the License is distributed on an "AS IS" BASIS,
emilmont 59:0883845fe643 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
emilmont 59:0883845fe643 13 * See the License for the specific language governing permissions and
emilmont 59:0883845fe643 14 * limitations under the License.
emilmont 44:24d45a770a51 15 */
simon.ford@mbed.co.uk 0:82220227f4fa 16 #ifndef MBED_ANALOGOUT_H
simon.ford@mbed.co.uk 0:82220227f4fa 17 #define MBED_ANALOGOUT_H
simon.ford@mbed.co.uk 0:82220227f4fa 18
emilmont 44:24d45a770a51 19 #include "platform.h"
emilmont 27:7110ebee3484 20
emilmont 27:7110ebee3484 21 #if DEVICE_ANALOGOUT
emilmont 27:7110ebee3484 22
emilmont 44:24d45a770a51 23 #include "analogout_api.h"
simon.ford@mbed.co.uk 0:82220227f4fa 24
simon.ford@mbed.co.uk 0:82220227f4fa 25 namespace mbed {
simon.ford@mbed.co.uk 0:82220227f4fa 26
emilmont 43:e2ed12d17f06 27 /** An analog output, used for setting the voltage on a pin
rolf.meyer@arm.com 11:1c1ebd0324fa 28 *
rolf.meyer@arm.com 11:1c1ebd0324fa 29 * Example:
emilmont 43:e2ed12d17f06 30 * @code
emilmont 43:e2ed12d17f06 31 * // Make a sawtooth output
emilmont 55:d722ed6a4237 32 *
emilmont 43:e2ed12d17f06 33 * #include "mbed.h"
emilmont 55:d722ed6a4237 34 *
emilmont 43:e2ed12d17f06 35 * AnalogOut tri(p18);
emilmont 43:e2ed12d17f06 36 * int main() {
emilmont 43:e2ed12d17f06 37 * while(1) {
emilmont 43:e2ed12d17f06 38 * tri = tri + 0.01;
emilmont 43:e2ed12d17f06 39 * wait_us(1);
emilmont 43:e2ed12d17f06 40 * if(tri == 1) {
emilmont 43:e2ed12d17f06 41 * tri = 0;
emilmont 43:e2ed12d17f06 42 * }
emilmont 43:e2ed12d17f06 43 * }
emilmont 43:e2ed12d17f06 44 * }
emilmont 43:e2ed12d17f06 45 * @endcode
simon.ford@mbed.co.uk 0:82220227f4fa 46 */
emilmont 44:24d45a770a51 47 class AnalogOut {
simon.ford@mbed.co.uk 0:82220227f4fa 48
simon.ford@mbed.co.uk 0:82220227f4fa 49 public:
simon.ford@mbed.co.uk 0:82220227f4fa 50
emilmont 43:e2ed12d17f06 51 /** Create an AnalogOut connected to the specified pin
emilmont 55:d722ed6a4237 52 *
emilmont 43:e2ed12d17f06 53 * @param AnalogOut pin to connect to (18)
emilmont 43:e2ed12d17f06 54 */
emilmont 44:24d45a770a51 55 AnalogOut(PinName pin) {
emilmont 44:24d45a770a51 56 analogout_init(&_dac, pin);
emilmont 44:24d45a770a51 57 }
emilmont 55:d722ed6a4237 58
emilmont 43:e2ed12d17f06 59 /** Set the output voltage, specified as a percentage (float)
rolf.meyer@arm.com 11:1c1ebd0324fa 60 *
emilmont 55:d722ed6a4237 61 * @param value A floating-point value representing the output voltage,
rolf.meyer@arm.com 11:1c1ebd0324fa 62 * specified as a percentage. The value should lie between
rolf.meyer@arm.com 11:1c1ebd0324fa 63 * 0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%).
emilmont 44:24d45a770a51 64 * Values outside this range will be saturated to 0.0f or 1.0f.
rolf.meyer@arm.com 11:1c1ebd0324fa 65 */
emilmont 44:24d45a770a51 66 void write(float value) {
emilmont 44:24d45a770a51 67 analogout_write(&_dac, value);
emilmont 44:24d45a770a51 68 }
emilmont 55:d722ed6a4237 69
emilmont 43:e2ed12d17f06 70 /** Set the output voltage, represented as an unsigned short in the range [0x0, 0xFFFF]
simon.ford@mbed.co.uk 5:62573be585e9 71 *
emilmont 43:e2ed12d17f06 72 * @param value 16-bit unsigned short representing the output voltage,
emilmont 44:24d45a770a51 73 * normalised to a 16-bit value (0x0000 = 0v, 0xFFFF = 3.3v)
simon.ford@mbed.co.uk 5:62573be585e9 74 */
emilmont 44:24d45a770a51 75 void write_u16(unsigned short value) {
emilmont 44:24d45a770a51 76 analogout_write_u16(&_dac, value);
emilmont 44:24d45a770a51 77 }
simon.ford@mbed.co.uk 5:62573be585e9 78
emilmont 43:e2ed12d17f06 79 /** Return the current output voltage setting, measured as a percentage (float)
simon.ford@mbed.co.uk 0:82220227f4fa 80 *
emilmont 43:e2ed12d17f06 81 * @returns
emilmont 55:d722ed6a4237 82 * A floating-point value representing the current voltage being output on the pin,
rolf.meyer@arm.com 11:1c1ebd0324fa 83 * measured as a percentage. The returned value will lie between
rolf.meyer@arm.com 11:1c1ebd0324fa 84 * 0.0f (representing 0v / 0%) and 1.0f (representing 3.3v / 100%).
rolf.meyer@arm.com 11:1c1ebd0324fa 85 *
emilmont 43:e2ed12d17f06 86 * @note
emilmont 43:e2ed12d17f06 87 * This value may not match exactly the value set by a previous write().
emilmont 44:24d45a770a51 88 */
emilmont 44:24d45a770a51 89 float read() {
emilmont 44:24d45a770a51 90 return analogout_read(&_dac);
emilmont 44:24d45a770a51 91 }
rolf.meyer@arm.com 11:1c1ebd0324fa 92
rolf.meyer@arm.com 11:1c1ebd0324fa 93 #ifdef MBED_OPERATORS
emilmont 43:e2ed12d17f06 94 /** An operator shorthand for write()
simon.ford@mbed.co.uk 0:82220227f4fa 95 */
emilmont 44:24d45a770a51 96 AnalogOut& operator= (float percent) {
emilmont 44:24d45a770a51 97 write(percent);
emilmont 44:24d45a770a51 98 return *this;
emilmont 44:24d45a770a51 99 }
emilmont 55:d722ed6a4237 100
emilmont 44:24d45a770a51 101 AnalogOut& operator= (AnalogOut& rhs) {
emilmont 44:24d45a770a51 102 write(rhs.read());
emilmont 44:24d45a770a51 103 return *this;
emilmont 44:24d45a770a51 104 }
simon.ford@mbed.co.uk 0:82220227f4fa 105
emilmont 43:e2ed12d17f06 106 /** An operator shorthand for read()
emilmont 44:24d45a770a51 107 */
emilmont 44:24d45a770a51 108 operator float() {
emilmont 44:24d45a770a51 109 return read();
emilmont 44:24d45a770a51 110 }
rolf.meyer@arm.com 11:1c1ebd0324fa 111 #endif
rolf.meyer@arm.com 11:1c1ebd0324fa 112
rolf.meyer@arm.com 11:1c1ebd0324fa 113 protected:
emilmont 44:24d45a770a51 114 dac_t _dac;
simon.ford@mbed.co.uk 0:82220227f4fa 115 };
simon.ford@mbed.co.uk 0:82220227f4fa 116
rolf.meyer@arm.com 11:1c1ebd0324fa 117 } // namespace mbed
simon.ford@mbed.co.uk 0:82220227f4fa 118
simon.ford@mbed.co.uk 1:6b7f447ca868 119 #endif
simon.ford@mbed.co.uk 1:6b7f447ca868 120
emilmont 27:7110ebee3484 121 #endif