Anand Tamariya / mbed

Important changes to repositories hosted on mbed.com

Mbed hosted mercurial repositories are deprecated and are due to be permanently deleted in July 2026.

To keep a copy of this software download the repository Zip archive or clone locally using Mercurial.

It is also possible to export all your personal repositories from the account settings page.

Fork of mbed by mbed official

PwmOut.h@27:7110ebee3484, 2011-11-29 (annotated)

Committer:
emilmont
Date:
Tue Nov 29 14:59:27 2011 +0000
Revision:
27:7110ebee3484
Parent:
18:b3c9f16cbb96
Child:
43:e2ed12d17f06
New Libraries 11.11

Who changed what in which revision?

UserRevisionLine numberNew contents of line
simon.ford@mbed.co.uk 0:82220227f4fa 1 /* mbed Microcontroller Library - PwmOut
emilmont 27:7110ebee3484 2 * Copyright (c) 2007-2011 ARM Limited. All rights reserved.
rolf.meyer@arm.com 11:1c1ebd0324fa 3 */
simon.ford@mbed.co.uk 0:82220227f4fa 4
simon.ford@mbed.co.uk 0:82220227f4fa 5 #ifndef MBED_PWMOUT_H
simon.ford@mbed.co.uk 0:82220227f4fa 6 #define MBED_PWMOUT_H
simon.ford@mbed.co.uk 0:82220227f4fa 7
emilmont 27:7110ebee3484 8 #include "device.h"
emilmont 27:7110ebee3484 9
emilmont 27:7110ebee3484 10 #if DEVICE_PWMOUT
emilmont 27:7110ebee3484 11
rolf.meyer@arm.com 11:1c1ebd0324fa 12 #include "platform.h"
rolf.meyer@arm.com 11:1c1ebd0324fa 13 #include "PinNames.h"
rolf.meyer@arm.com 11:1c1ebd0324fa 14 #include "PeripheralNames.h"
simon.ford@mbed.co.uk 0:82220227f4fa 15 #include "Base.h"
simon.ford@mbed.co.uk 0:82220227f4fa 16
simon.ford@mbed.co.uk 0:82220227f4fa 17 namespace mbed {
simon.ford@mbed.co.uk 0:82220227f4fa 18
simon.ford@mbed.co.uk 0:82220227f4fa 19 /* Class: PwmOut
simon.ford@mbed.co.uk 0:82220227f4fa 20 * A pulse-width modulation digital output
simon.ford@mbed.co.uk 5:62573be585e9 21 *
rolf.meyer@arm.com 11:1c1ebd0324fa 22 * Example
rolf.meyer@arm.com 11:1c1ebd0324fa 23 * > // Fade a led on.
rolf.meyer@arm.com 11:1c1ebd0324fa 24 * > #include "mbed.h"
rolf.meyer@arm.com 11:1c1ebd0324fa 25 * >
rolf.meyer@arm.com 11:1c1ebd0324fa 26 * > PwmOut led(LED1);
rolf.meyer@arm.com 11:1c1ebd0324fa 27 * >
rolf.meyer@arm.com 11:1c1ebd0324fa 28 * > int main() {
rolf.meyer@arm.com 11:1c1ebd0324fa 29 * > while(1) {
rolf.meyer@arm.com 11:1c1ebd0324fa 30 * > led = led + 0.01;
rolf.meyer@arm.com 11:1c1ebd0324fa 31 * > wait(0.2);
rolf.meyer@arm.com 11:1c1ebd0324fa 32 * > if(led == 1.0) {
rolf.meyer@arm.com 11:1c1ebd0324fa 33 * > led = 0;
rolf.meyer@arm.com 11:1c1ebd0324fa 34 * > }
rolf.meyer@arm.com 11:1c1ebd0324fa 35 * > }
rolf.meyer@arm.com 11:1c1ebd0324fa 36 * > }
simon.ford@mbed.co.uk 18:b3c9f16cbb96 37 *
simon.ford@mbed.co.uk 18:b3c9f16cbb96 38 * Note that on the LPC1768 and LPC2368, the PWMs all share the same
simon.ford@mbed.co.uk 18:b3c9f16cbb96 39 * period - if you change the period for one, you change it for all.
simon.ford@mbed.co.uk 18:b3c9f16cbb96 40 * Although routines that change the period maintain the duty cycle
simon.ford@mbed.co.uk 18:b3c9f16cbb96 41 * for its PWM, all other PWMs will require their duty cycle to be
simon.ford@mbed.co.uk 18:b3c9f16cbb96 42 * refreshed.
simon.ford@mbed.co.uk 0:82220227f4fa 43 */
simon.ford@mbed.co.uk 0:82220227f4fa 44 class PwmOut : public Base {
simon.ford@mbed.co.uk 0:82220227f4fa 45
simon.ford@mbed.co.uk 0:82220227f4fa 46 public:
simon.ford@mbed.co.uk 0:82220227f4fa 47
rolf.meyer@arm.com 11:1c1ebd0324fa 48 /* Constructor: PwmOut
rolf.meyer@arm.com 11:1c1ebd0324fa 49 * Create a PwmOut connected to the specified pin
rolf.meyer@arm.com 11:1c1ebd0324fa 50 *
rolf.meyer@arm.com 11:1c1ebd0324fa 51 * Variables:
rolf.meyer@arm.com 11:1c1ebd0324fa 52 * pin - PwmOut pin to connect to
rolf.meyer@arm.com 11:1c1ebd0324fa 53 */
rolf.meyer@arm.com 11:1c1ebd0324fa 54 PwmOut(PinName pin, const char *name = NULL);
simon.ford@mbed.co.uk 0:82220227f4fa 55
rolf.meyer@arm.com 11:1c1ebd0324fa 56 /* Function: write
rolf.meyer@arm.com 11:1c1ebd0324fa 57 * Set the ouput duty-cycle, specified as a percentage (float)
rolf.meyer@arm.com 11:1c1ebd0324fa 58 *
rolf.meyer@arm.com 11:1c1ebd0324fa 59 * Variables:
rolf.meyer@arm.com 11:1c1ebd0324fa 60 * value - A floating-point value representing the output duty-cycle,
rolf.meyer@arm.com 11:1c1ebd0324fa 61 * specified as a percentage. The value should lie between
rolf.meyer@arm.com 11:1c1ebd0324fa 62 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
rolf.meyer@arm.com 11:1c1ebd0324fa 63 * Values outside this range will be saturated to 0.0f or 1.0f.
rolf.meyer@arm.com 11:1c1ebd0324fa 64 */
rolf.meyer@arm.com 11:1c1ebd0324fa 65 void write(float value);
simon.ford@mbed.co.uk 0:82220227f4fa 66
rolf.meyer@arm.com 11:1c1ebd0324fa 67 /* Function: read
rolf.meyer@arm.com 11:1c1ebd0324fa 68 * Return the current output duty-cycle setting, measured as a percentage (float)
simon.ford@mbed.co.uk 0:82220227f4fa 69 *
simon.ford@mbed.co.uk 0:82220227f4fa 70 * Variables:
rolf.meyer@arm.com 11:1c1ebd0324fa 71 * returns - A floating-point value representing the current duty-cycle being output on the pin,
rolf.meyer@arm.com 11:1c1ebd0324fa 72 * measured as a percentage. The returned value will lie between
rolf.meyer@arm.com 11:1c1ebd0324fa 73 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
rolf.meyer@arm.com 11:1c1ebd0324fa 74 *
rolf.meyer@arm.com 11:1c1ebd0324fa 75 * Note:
rolf.meyer@arm.com 11:1c1ebd0324fa 76 * This value may not match exactly the value set by a previous <write>.
rolf.meyer@arm.com 11:1c1ebd0324fa 77 */
simon.ford@mbed.co.uk 0:82220227f4fa 78 float read();
rolf.meyer@arm.com 11:1c1ebd0324fa 79
rolf.meyer@arm.com 11:1c1ebd0324fa 80 /* Function: period
simon.ford@mbed.co.uk 18:b3c9f16cbb96 81 * Set the PWM period, specified in seconds (float), keeping the
simon.ford@mbed.co.uk 18:b3c9f16cbb96 82 * duty cycle the same.
simon.ford@mbed.co.uk 18:b3c9f16cbb96 83 *
simon.ford@mbed.co.uk 18:b3c9f16cbb96 84 * Note:
simon.ford@mbed.co.uk 18:b3c9f16cbb96 85 * The resolution is currently in microseconds; periods smaller than this
simon.ford@mbed.co.uk 18:b3c9f16cbb96 86 * will be set to zero.
rolf.meyer@arm.com 11:1c1ebd0324fa 87 */
rolf.meyer@arm.com 11:1c1ebd0324fa 88 void period(float seconds);
simon.ford@mbed.co.uk 0:82220227f4fa 89
rolf.meyer@arm.com 11:1c1ebd0324fa 90 /* Function: period_ms
simon.ford@mbed.co.uk 18:b3c9f16cbb96 91 * Set the PWM period, specified in milli-seconds (int), keeping the
simon.ford@mbed.co.uk 18:b3c9f16cbb96 92 * duty cycle the same.
rolf.meyer@arm.com 11:1c1ebd0324fa 93 */
rolf.meyer@arm.com 11:1c1ebd0324fa 94 void period_ms(int ms);
simon.ford@mbed.co.uk 5:62573be585e9 95
rolf.meyer@arm.com 11:1c1ebd0324fa 96 /* Function: period_us
simon.ford@mbed.co.uk 18:b3c9f16cbb96 97 * Set the PWM period, specified in micro-seconds (int), keeping the
simon.ford@mbed.co.uk 18:b3c9f16cbb96 98 * duty cycle the same.
rolf.meyer@arm.com 11:1c1ebd0324fa 99 */
rolf.meyer@arm.com 11:1c1ebd0324fa 100 void period_us(int us);
simon.ford@mbed.co.uk 5:62573be585e9 101
rolf.meyer@arm.com 11:1c1ebd0324fa 102 /* Function: pulsewidth
simon.ford@mbed.co.uk 18:b3c9f16cbb96 103 * Set the PWM pulsewidth, specified in seconds (float), keeping the
simon.ford@mbed.co.uk 18:b3c9f16cbb96 104 * period the same.
rolf.meyer@arm.com 11:1c1ebd0324fa 105 */
rolf.meyer@arm.com 11:1c1ebd0324fa 106 void pulsewidth(float seconds);
rolf.meyer@arm.com 11:1c1ebd0324fa 107
rolf.meyer@arm.com 11:1c1ebd0324fa 108 /* Function: pulsewidth_ms
simon.ford@mbed.co.uk 18:b3c9f16cbb96 109 * Set the PWM pulsewidth, specified in milli-seconds (int), keeping
simon.ford@mbed.co.uk 18:b3c9f16cbb96 110 * the period the same.
rolf.meyer@arm.com 11:1c1ebd0324fa 111 */
rolf.meyer@arm.com 11:1c1ebd0324fa 112 void pulsewidth_ms(int ms);
rolf.meyer@arm.com 11:1c1ebd0324fa 113
rolf.meyer@arm.com 11:1c1ebd0324fa 114 /* Function: pulsewidth_us
simon.ford@mbed.co.uk 18:b3c9f16cbb96 115 * Set the PWM pulsewidth, specified in micro-seconds (int), keeping
simon.ford@mbed.co.uk 18:b3c9f16cbb96 116 * the period the same.
rolf.meyer@arm.com 11:1c1ebd0324fa 117 */
rolf.meyer@arm.com 11:1c1ebd0324fa 118 void pulsewidth_us(int us);
simon.ford@mbed.co.uk 0:82220227f4fa 119
rolf.meyer@arm.com 11:1c1ebd0324fa 120 #ifdef MBED_OPERATORS
rolf.meyer@arm.com 11:1c1ebd0324fa 121 /* Function: operator=
rolf.meyer@arm.com 11:1c1ebd0324fa 122 * A operator shorthand for <write()>
rolf.meyer@arm.com 11:1c1ebd0324fa 123 */
rolf.meyer@arm.com 11:1c1ebd0324fa 124 PwmOut& operator= (float value);
rolf.meyer@arm.com 11:1c1ebd0324fa 125 PwmOut& operator= (PwmOut& rhs);
simon.ford@mbed.co.uk 0:82220227f4fa 126
rolf.meyer@arm.com 11:1c1ebd0324fa 127 /* Function: operator float()
rolf.meyer@arm.com 11:1c1ebd0324fa 128 * An operator shorthand for <read()>
rolf.meyer@arm.com 11:1c1ebd0324fa 129 */
rolf.meyer@arm.com 11:1c1ebd0324fa 130 operator float();
rolf.meyer@arm.com 11:1c1ebd0324fa 131 #endif
simon.ford@mbed.co.uk 4:5d1359a283bc 132
rolf.meyer@arm.com 11:1c1ebd0324fa 133 #ifdef MBED_RPC
simon.ford@mbed.co.uk 5:62573be585e9 134 virtual const struct rpc_method *get_rpc_methods();
simon.ford@mbed.co.uk 5:62573be585e9 135 static struct rpc_class *get_rpc_class();
rolf.meyer@arm.com 11:1c1ebd0324fa 136 #endif
simon.ford@mbed.co.uk 5:62573be585e9 137
simon.ford@mbed.co.uk 0:82220227f4fa 138 protected:
simon.ford@mbed.co.uk 0:82220227f4fa 139
rolf.meyer@arm.com 11:1c1ebd0324fa 140 PWMName _pwm;
rolf.meyer@arm.com 11:1c1ebd0324fa 141
simon.ford@mbed.co.uk 0:82220227f4fa 142 };
simon.ford@mbed.co.uk 0:82220227f4fa 143
rolf.meyer@arm.com 11:1c1ebd0324fa 144 } // namespace mbed
simon.ford@mbed.co.uk 0:82220227f4fa 145
simon.ford@mbed.co.uk 1:6b7f447ca868 146 #endif
emilmont 27:7110ebee3484 147
emilmont 27:7110ebee3484 148 #endif