Hi Resolution, Modulated One-Shot Definition

Use this MotoHawk™ block to generate a one-shot pulse, as configured via block inputs. The pulse has up to 2 periods possible, in which 2 different PWM modulations can be generated.

Block ID

motohawk_hires_oneshot

Library

MotoHawk_lib/Advanced Digital I/O

Description

Inputs

The resource is asserted in a one-shot manner when the Trigger input is TRUE.

The output pulse has 2 periods in which 2 different PWM modulations are generated. Each period is described by Duration, Duty Cycle and Frequency. The second portion of the pulse is not generated if the second period duration is zero. Only the second portion is generated if the first period is zero.

A new on shot pulse won't be triggered if the block is executed with the Trigger input set to FALSE. A trigger input of TRUE is ignored if the one shot hasn't completed both portions from a previous trigger. The one shot will not re-trigger.

The pulse is cancelled when the Cancel input is set to TRUE, but will continue or can be retriggered if FALSE.

Duration is in microseconds, Duty Cycle is in a range of -4096 to 4096 where 0 is 0%, 4096 is 100%, and Frequency is in Hz.

The absolute value of the dutycycle is taken internally and so a negative value serves no purpose. It is signed only to remain compatible with other Duty Cycle signals used throughout MotoHawk™

Max Expected Duration (ms)

MotoHawk™ uses Max Expected Duration attribute, which can be set on the mask, to assist it in configuring its internal data representation and clocks so as to achieve the requested duration whilst maximizing the achievable resolution of the PWM modulation aspect of the pulse. Set this attribute to a value that exceeds the maximum period that a pulse portion would be expected to deliver.

This value does not explicitly define what the maximum duration that a pulse portion can take on and so a value of 100ms may still mean that a pulse portion longer than this is achievable. However it can result in premature clipping if set too small. See module considerations for further details on what duration can be delivered.

Block Parameters

Parameter Field	Values	Comments/Description
Name	single-quote enclosed alpha-numeric text	Name of block, for reference.  No special characters, such as spaces, dashes, commas (underscore allowed).
Resource	Drop-down list	Select resource that will output the one-shot signal.
Max Expected Duration (ms)	Positive integer	See Max Expected Duration section above.
Allow I/O pin to be calibrated	Check box (enable)	Name, Access Levels and Group Strings fields available. This field is only available on Classic modules, see ModuleTypes for help.
Calibration Name	Alpha-numeric text, single-quote enclosed.	Name of output, for reference.  No special characters, such as spaces, dashes, commas (underscore allowed).
Read Access Level	0-8	Sets security level 1 lowest, 8 highest, for user access to read value. A setting of zero indicates unsecured access is allowed.
Write Access Level	0-8	Sets security level 1 lowest, 8 highest, for user access to write value. A setting of zero indicates unsecured access is allowed.
Group String	Alpha-numeric text, single-quote enclosed	Determines Folder name and hierarchy. Use "|" character between folder names to delineate subfolder structure.