Difference between revisions of "Unit PWM"

From Ultibo.org
Jump to: navigation, search
Line 427: Line 427:
 
! '''Note'''
 
! '''Note'''
 
| To be documented
 
| To be documented
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
 +
'''RTL PWM functions'''
 +
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMAvailable:Boolean; </pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Check if a PWM device is available</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''Note'''
 +
| To be documented
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMStart:LongWord;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Start the default PWM device</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''Return'''
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMStop:LongWord;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Stop the default PWM device</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''Return'''
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMWrite(Value:LongWord):LongWord;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Write a value to the default PWM device</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''Value'''
 +
| The value to write
 +
|-
 +
! '''Return'''
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
! '''Note'''
 +
| The exact meaning of value may depend on the device and other configured options, in many cases the value will represent the "on" time of each pulse with regard to the duty cycle of the waveform output by the device
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMSetMode(Mode:LongWord):LongWord;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Set the mode for the default PWM device</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''Mode'''
 +
| The mode value to set (eg PWM_MODE_MARKSPACE)
 +
|-
 +
! '''Return'''
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMSetRange(Range:LongWord):LongWord;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Set the range for the default PWM device</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''Range'''
 +
| The range value to set
 +
|-
 +
! '''Return'''
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
! '''Note'''
 +
| The exact meaning of range may depend on the device and other configured options, in many cases the range will represent the period of one full cycle of the waveform output by the device
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMSetFrequency(Frequency:LongWord):LongWord;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Set the clock frequency for the default PWM device</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''Frequency'''
 +
| The frequency to set in Hz
 +
|-
 +
! '''Return'''
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function SysPWMConfigure(DutyNS,PeriodNS:LongWord):LongWord;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Set the configuration of the default PWM device</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! '''DutyNS'''
 +
| The "on" time part of the cycle (Nanoseconds)
 +
|-
 +
! '''PeriodNS'''
 +
| The duration of one full cycle (Nanoseconds)
 +
|-
 +
! '''Return'''
 +
| ERROR_SUCCESS if completed or another error code on failure
 
|-
 
|-
 
|}
 
|}

Revision as of 04:09, 2 September 2016

Return to Unit Reference


Description


Pulse Width Modulation (PWM) is a technique of encoding a pulsed signal so as to control the ratio of on to off by switching the signal between on and off at a very high rate.

This on and off switching allows control of the average power supplied to the load and therefore gives fine grained control of things such as motor speeds, lamp dimming and heating elements.

PWM is also used in many low power applications as well such as controlling servo motors and can even by used for audio applications such as class D amplifiers.

This unit deals with the usage of PWM for control applications (for audio applications see the Audio unit) and provides methods to control the state, frequency, duty cycle, range and mode of PWM host controllers. Not all devices support all of these concepts so this API includes a properties function to allow obtaining information about a PWM device and its capabilities.

Constants

To be documented

Type definitions

To be documented

Public variables

To be documented

Function declarations


Initialization functions

[Expand] 
procedure PWMInit;
Description: Initialize the PWM unit and PWM device table


PWM functions

[Expand] 
function PWMDeviceStart(PWM:PPWMDevice):LongWord;
Description: Start the specified PWM device


[Expand] 
function PWMDeviceStop(PWM:PPWMDevice):LongWord;
Description: Stop the specified PWM device


[Expand] 
function PWMDeviceWrite(PWM:PPWMDevice; Value:LongWord):LongWord;
Description: Write a value to the specified PWM device


[Expand] 
function PWMDeviceGetGPIO(PWM:PPWMDevice):LongWord;
Description: Get the GPIO pin used by the specified PWM device


[Expand] 
function PWMDeviceSetGPIO(PWM:PPWMDevice; GPIO:LongWord):LongWord;
Description: Set the GPIO pin used by the specified PWM device


[Expand] 
function PWMDeviceGetMode(PWM:PPWMDevice):LongWord;
Description: Get the current mode of the specified PWM device


[Expand] 
function PWMDeviceSetMode(PWM:PPWMDevice; Mode:LongWord):LongWord;
Description: Set the current mode for the specified PWM device


[Expand] 
function PWMDeviceGetRange(PWM:PPWMDevice):LongWord;
Description: Get the current range of the specified PWM device


[Expand] 
function PWMDeviceSetRange(PWM:PPWMDevice; Range:LongWord):LongWord;
Description: Set the current range for the specified PWM device


[Expand] 
function PWMDeviceGetFrequency(PWM:PPWMDevice):LongWord;
Description: Get the clock frequency of the specified PWM device


[Expand] 
function PWMDeviceSetFrequency(PWM:PPWMDevice; Frequency:LongWord):LongWord;
Description: Set the clock frequency for the specified PWM device


[Expand] 
function PWMDeviceGetPolarity(PWM:PPWMDevice):LongWord;
Description: Get the current polarity of the specified PWM device


[Expand] 
function PWMDeviceSetPolarity(PWM:PPWMDevice; Polarity:LongWord):LongWord;
Description: Set the current polarity for the specified PWM device


[Expand] 
function PWMDeviceConfigure(PWM:PPWMDevice; DutyNS,PeriodNS:LongWord):LongWord;
Description: Set the configuration of the specified PWM device


[Expand] 
function PWMDeviceProperties(PWM:PPWMDevice; Properties:PPWMProperties):LongWord;
Description: Get the properties for the specified PWM device


[Expand] 
function PWMDeviceCreate:PPWMDevice;
Description: Create a new PWM entry


[Expand] 
function PWMDeviceCreateEx(Size:LongWord):PPWMDevice;
Description: Create a new PWM entry


[Expand] 
function PWMDeviceDestroy(PWM:PPWMDevice):LongWord;
Description: Destroy an existing PWM entry


[Expand] 
function PWMDeviceRegister(PWM:PPWMDevice):LongWord;
Description: Register a new PWM in the PWM table


[Expand] 
function PWMDeviceDeregister(PWM:PPWMDevice):LongWord;
Description: Deregister a PWM from the PWM table


[Expand] 
function PWMDeviceFind(PWMId:LongWord):PPWMDevice;
Description: To be documented


[Expand] 
function PWMDeviceFindByName(const Name:String):PPWMDevice; inline;
Description: To be documented


[Expand] 
function PWMDeviceFindByDescription(const Description:String):PPWMDevice; inline;
Description: To be documented


[Expand] 
function PWMDeviceEnumerate(Callback:TPWMEnumerate; Data:Pointer):LongWord;
Description: To be documented


[Expand] 
function PWMDeviceNotification(PWM:PPWMDevice; Callback:TPWMNotification; Data:Pointer; Notification,Flags:LongWord):LongWord;
Description: To be documented


RTL PWM functions

[Expand] 
function SysPWMAvailable:Boolean;
Description: Check if a PWM device is available


[Expand] 
function SysPWMStart:LongWord;
Description: Start the default PWM device


[Expand] 
function SysPWMStop:LongWord;
Description: Stop the default PWM device


[Expand] 
function SysPWMWrite(Value:LongWord):LongWord;
Description: Write a value to the default PWM device


[Expand] 
function SysPWMSetMode(Mode:LongWord):LongWord;
Description: Set the mode for the default PWM device


[Expand] 
function SysPWMSetRange(Range:LongWord):LongWord;
Description: Set the range for the default PWM device


[Expand] 
function SysPWMSetFrequency(Frequency:LongWord):LongWord;
Description: Set the clock frequency for the default PWM device


[Expand] 
function SysPWMConfigure(DutyNS,PeriodNS:LongWord):LongWord;
Description: Set the configuration of the default PWM device



Return to Unit Reference

Retrieved from "https://ultibo.org/mediawiki_ultibo_org/index.php?title=Unit_PWM&oldid=539"