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- Phidgets.Phidget.Phidget
-
- Encoder
class Encoder(Phidgets.Phidget.Phidget) |
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This class represents a Phidget Encoder. All methods to read encoder data from an encoder are implemented in this class.
Phidget Encoder boards generally support 1 or more encoders with 0 or more digital inputs. Both high speed optical and low speed mechanical encoders are supported with this API.
See your device's User Guide for more specific API details, technical information, and revision details.
The User Guide, along with other resources, can be found on the product page for your device.
Extends:
Phidget
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Methods defined here:
- __del__(self)
- The Destructor Method for the Encoder Class
- __init__(self)
- The Constructor Method for the Encoder Class
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened.
- getEnabled(self, index)
- Gets the enabled state of an encoder.
Returns whether power to the encoder is enabled or disabled.
Parameters:
index<int>: index of the encoder.
Returns:
The enabled state of the encoder <boolean>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached, or if the index is out of range.
- getEncoderCount(self)
- Returns number of encoders.
All current encoder boards support one encoder.
Returns:
The number of encoders <int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached.
- getIndexPosition(self, index)
- Gets the index position for an encoder that supports index.
For encoders that support index position, this function will return the index position for the encoder connected at the provided index.
Parameters:
index<int>: index of the encoder.
Returns:
The index position of the encoder <int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached, or if the index is out of range.
- getInputCount(self)
- Returns number of digital inputs.
On the mechanical encoder this refers to the pushbutton.
The high speed encoder does not have any digital inputs.
Returns:
The number of inputs <int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached.
- getInputState(self, index)
- Returns the state of a digital input.
On the mechanical encoder this refers to the pushbutton.
The high speed encoder does not have any digital inputs. A value of true means that the input is active(the button is pushed).
Parameters:
index<int>: index of the input.
Returns:
The state of the input <boolean>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached, or if the index is out of range.
- getPosition(self, index)
- Returns the position of an encoder.
This is an absolute position as calcutated since the encoder was plugged in.
This value can be reset to anything using setPosition.
Parameters:
index<int>: index of the encoder.
Returns:
The position of the encoder <int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached, or if the index is out of range.
- setEnabled(self, index, state)
- Sets the enabled state of an encoder.
The enabled state controls whether to enable or disable power to the encoder.
Parameters:
index<int>: Index of the motor.
state<boolean>: State to set the enabled state for this encoder to.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached, or if the index is out of range.
- setOnInputChangeHandler(self, inputChangeHandler)
- Sets the input change event handler.
The input change handler is a method that will be called when an input on this Encoder board has changed.
Parameters:
inputChangeHandler: hook to the inputChangeHandler callback function.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException
- setOnPositionChangeHandler(self, positionChangeHandler)
- Sets the position change event handler.
The position change handler is a method that will be called when the position of an encoder changes.
The position change event provides data about how many ticks have occured, and how much time has passed since the last position change event,
but does not contain an absolute position.
This can be obtained from getEncoderPosition.
Parameters:
positionChangeHandler: hook to the positionChangeHandler callback function.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException
- setPosition(self, index, position)
- Sets the position of a specific encoder.
This resets the internal position count for an encoder.
This call in no way actually sends information to the device, as an absolute position is maintained only in the library.
After this call, position changes from the encoder will use the new value to calculate absolute position as reported by the change handler.
Parameters:
index<int>: index of the encoder.
position<position>: new position for this encoder.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached, or if the index is out of range.
Methods inherited from Phidgets.Phidget.Phidget:
- closePhidget(self)
- Closes this Phidget.
This will shut down all threads dealing with this Phidget and you won't recieve any more events.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened.
- getDeviceClass(self)
- Gets the class of this Phidget.
Classes represent a group of Phidgets that use the same API type.
Returns:
The Device Class number<int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If there is no Phidget attached.
- getDeviceID(self)
- Gets the ID of this Phidget.
This ID specifies a specific Phidget device, within the phidget class.
Returns:
The Device ID <int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If there is no Phidget attached.
- getDeviceLabel(self)
- Gets the label associated with this Phidget.
This label is a String - up to ten digits - that is stored in the Flash memory of newer Phidgets.
This label can be set programatically (see setDeviceLabel), and is non-volatile - so it is remembered even if the Phidget is unplugged.
Returns:
The label associated with this Phidget <string>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached, or if this Phidget does not support labels.
- getDeviceName(self)
- Return the name of this Phidget.
This is a string that describes the device. For example, a PhidgetInterfaceKit
could be described as "Phidget InterfaceKit 8/8/8", or "Phidget InterfaceKit 0/0/4", among others, depending on the specific device.
This lets you determine the specific type of a Phidget, within the broader classes of Phidgets, such as PhidgetInterfaceKit, or PhidgetServo.
Returns:
The name of the device <string>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this phidget is not opened or attached.
- getDeviceType(self)
- Return the device type of this Phidget.
This is a string that describes the device as a class of devices. For example, all PhidgetInterfaceKit Phidgets
will returns the String "PhidgetInterfaceKit".
Returns:
The Device Type <string>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If there is no Phidget attached.
- getDeviceVersion(self)
- Returns the device version of this Phidget.
This number is simply a way of distinguishing between different revisions of a specific type of Phidget, and is
only really of use if you need to troubleshoot device problems with Phidgets Inc.
Returns:
The Device Version <int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If there is no Phidget attached.
- getLibraryVersion(self)
- Returns the library version.
This is the library version of the underlying phidget21 C library and not the version of the Python wrapper module implementation.
The version is retured as a string which contains the version number and build date.
Returns:
The Library Version <string>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached.
- getSerialNum(self)
- Returns the unique serial number of this Phidget.
This number is set during manufacturing, and is unique across all Phidgets. This number can be used in calls to open to specify this specific Phidget to be opened.
Returns:
The Serial Number <int>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened and attached.
- getServerAddress(self)
- Returns the Address of a Phidget Webservice.
Returns the Address of a Phidget Webservice when this Phidget was opened as remote.
This may be an IP Address or a hostname.
Returns:
The Address of the Webservice <string>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: if this Phidget was open opened as a remote Phidget.
- getServerID(self)
- Returns the Server ID of a Phidget Webservice.
Returns the Server ID of a Phidget Webservice when this Phidget was opened as remote.
This is an arbitrary server identifier, independant of IP address and Port.
Returns:
The ServerID of the Webservice <string>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: if this Phidget was open opened as a remote Phidget.
- isAttached(self)
- Returns the attached status of this Phidget.
This method returns True or False, depending on whether the Phidget is phisically plugged into the computer, initialized, and ready to use - or not.
If a Phidget is not attached, many functions calls will fail with a PhidgetException, so either checking this function, or using the Attach and Detach events, is recommended, if a device is likely to be attached or detached during use.
Returns:
Attached Status of the Phidget <boolean>
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened.
- isAttachedToServer(self)
- Returns the network attached status for remotely opened Phidgets.
This method returns True or False, depending on whether a connection to the Phidget WebService is open - or not.
If this is false for a remote Phidget then the connection is not active - either because a connection has not yet been established,
or because the connection was terminated.
Returns:
Phidget Network Attached Status <boolean>.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened remotely.
- openPhidget(self, serial=-1)
- Open a Phidget with or without a serial number.
Open is pervasive. What this means is that you can call open on a device before it is plugged in, and keep the device opened across device dis- and re-connections.
Open is Asynchronous. What this means is that open will return immediately -- before the device being opened is actually available,
so you need to use either the attach event or the waitForAttachment method to determine if a device is available before using it.
If no arguement is provided, the first available Phidget will be opened. If there are two Phidgets of the same type attached to the system,
you should specify a serial number, as there is no guarantee which Phidget will be selected by the call to open().
The serial number is a unique number assigned to each Phidget during production and can be used to uniquely identify specific phidgets.
Parameters:
serial<int>: The serial number of the device
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException
- openRemote(self, serverID, serial=-1, password='')
- Open this Phidget remotely using a Server ID, securely providing a password, and whether or not to connect to a specific serial number.
Providing a password will open the connection securely depending on if a password is set on the host machine's webservice.
If no serial number is provided, the first available Phidget will be opened. If there are two Phidgets of the same type attached to the system,
you should specify a serial number, as there is no guarantee which Phidget will be selected by the call to open().
Parameters:
serverID<string>: ServerID of the Phidget Webservice
serial<int>: The serial number of the device
password<string>: The secure password for the Phidget Webservice
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: if the Phidget Webservice cannot be contacted
- openRemoteIP(self, IPAddress, port, serial=-1, password='')
- Open this Phidget remotely using an IP Address, securely providing a password,and whether or not to connect to a specific serial number.
Providing a password will open the connection securely depending on if a password is set on the host machine's webservice.
If no serial number is provided, the first available Phidget will be opened. If there are two Phidgets of the same type attached to the system,
you should specify a serial number, as there is no guarantee which Phidget will be selected by the call to open().
Parameters:
IPAddress<string>: IP Address or hostname of the Phidget Webservice
port<int>: Port of the Phidget Webservice
serial<int>: The serial number of the device
password<string>: The secure password for the Phidget Webservice
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: if the Phidget Webservice cannot be contacted
- setOnAttachHandler(self, attachHandler)
- Sets the Attach Event Handler.
The attach handler is a method that will be called when this Phidget is physically attached to the system, and has gone through its initalization, and so is ready to be used.
Parameters:
attachHandler: hook to the attachHandler callback function
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened.
- setOnDetachHandler(self, detachHandler)
- Sets the Detach Event Handler.
The detach handler is a method that will be called when this Phidget is phisically detached from the system, and is no longer available.
This is particularly usefull for applications when a phisical detach would be expected.
Remember that many of the methods, if called on an unattached device, will throw a PhidgetException.
This Exception can be checked to see if it was caused by a device being unattached, but a better method would be to regiter the detach handler,
which could notify the main program logic that the device is no longer available, disable GUI controls, etc.
Parameters:
detachHandler: hook to the detachHandler callback function
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened.
- setOnErrorhandler(self, errorHandler)
- Sets the Error Event Handler.
The error handler is a method that will be called when an asynchronous error occurs.
Error events are not currently used, but will be in the future to report any problems that happen out of context from a direct function call.
Parameters:
errorHandler: hook to the errorHandler callback function.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened.
- setOnServerConnectHandler(self, serverConnectHandler)
- Sets the Server Connect Event Handler.
The serverConnect handler is a method that will be called when a connection to a server is made. This is only usefull for Phidgets opened remotely.
Parameters:
serverConnectHandler: hook to the serverConnectHandler callback function
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened
- setOnServerDisconnectHandler(self, serverDisconnectHandler)
- Set the Server Disconnect event handler.
The serverDisconnect handler is a method that will be called when a connection to a server is terminated. This is only usefull for Phidgets opened remotely.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened
- waitForAttach(self, timeout)
- Waits for this Phidget to become available.
This method can be called after open has been called to wait for thid Phidget to become available.
This is usefull because open is asynchronous (and thus returns immediately), and most methods will throw a PhidgetException is they are called before a device is actually ready.
This method is synonymous with polling the isAttached method until it returns True, or using the Attach event.
This method blocks for up to the timeout, at which point it will throw a PhidgetException. Otherwise, it returns when the phidget is attached and initialized.
A timeout of 0 is infinite.
Parameters:
timeout<long>: Timeout in milliseconds
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException: If this Phidget is not opened.
Static methods inherited from Phidgets.Phidget.Phidget:
- disableLogging()
- Turns off logging in the native C Library.
This only needs to be called if enableLogging was called to turn logging on.
This will turn logging back off.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException
- dispose(self)
- enableLogging(level, file)
- Turns on logging in the native C Library.
This is mostly usefull for debugging purposes - when an issue needs to be resolved by Phidgets Inc.
The output is mostly low-level library information, that won't be usefull for most users.
Logging may be usefull for users trying to debug their own problems, as logs can be inserted by the user using log.
The level can be one of:
PhidgetLogLevel.PHIDGET_LOG_VERBOSE ,
PhidgetLogLevel.PHIDGET_LOG_INFO ,
PhidgetLogLevel.PHIDGET_LOG_DEBUG ,
PhidgetLogLevel.PHIDGET_LOG_WARNING ,
PhidgetLogLevel.PHIDGET_LOG_ERROR or
PhidgetLogLevel.PHIDGET_LOG_CRITICAL
Parameters:
level<int>: highest level of logging that will be output, the PhidgetLogLevel object has been provided for a readable way to set this.
file<string>: path and name of file to output to. specify NULL to output to the console.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException
- log(level, id, log)
- Adds a log entry into the phidget log.
This log is enabled by calling enableLogging and this allows the entry of user logs in amongst the phidget library logs.
The level can be one of:
PhidgetLogLevel.PHIDGET_LOG_VERBOSE,
PhidgetLogLevel.PHIDGET_LOG_INFO,
PhidgetLogLevel.PHIDGET_LOG_DEBUG,
PhidgetLogLevel.PHIDGET_LOG_WARNING,
PhidgetLogLevel.PHIDGET_LOG_ERROR or
PhidgetLogLevel.PHIDGET_LOG_CRITICAL
Note: PhidgetLogLevel.PHIDGET_LOG_DEBUG should not be used, as these logs are only printed when using the debug library,
which is not generally available.
Parameters:
level<int>: level to enter the log at.
id<string>: an arbitrary identifier for this log. This can be NULL. The C library uses this field for source filename and line number.
log<string>: the message to log.
Exceptions:
RuntimeError - If current platform is not supported/phidget c dll cannot be found
PhidgetException
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