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HA0302T Rev A Feb 2016
Chapter 5
Persist Settings to Hardware -
Many of the parameters that can be set for the RBD201
series drivers can be stored (persisted) within the unit itself, such that when the unit
is next powered up these settings are applied automatically. This is particularly
important when the driver is being used manually via a joystick, in the absence of a
PC and USB link. The
Motor Output, Position Profiling Tracking & Settling, and
Joystick
parameters described previously are good examples of settings that can be
altered and then persisted in the driver for later use.
To save the settings to hardware, check the ‘Persist Settings to Hardware’ checkbox
before clicking the ‘OK button.
Triggering
External triggering is facilitated by the Trigger In and Trigger Out pins (pins 2 and 3)
of the USER IO connector on the rear panel of the unit - see Section A.4.
These connectors allow the connection of external TTL compatible signals to initiate
moves (Trigger In) and generate a hardware signal when certain motion related
conditions are met (Trigger Out). They provide a 5V logic level input and output that
can be configured to support triggering from and to external devices.
It is possible to configure a particular controller to respond to trigger inputs, generate
trigger outputs or both simultaneously. For those units configured for both input and
output triggering, a move can be initiated via a trigger input while at the same time, a
trigger output can be generated to initiate a move on another unit.
The trigger settings can be used to configure multiple units in a master – slave set up,
thereby allowing multiple channels of motion to be synchronized. Multiple moves can
then be initiated via a single software or hardware trigger command.
Trigger In
The Trigger In input can be configured to initiate a relative, absolute or homing home,
either on the rising or falling edge of the signal driving it. As the trigger input is edge
sensitive, it needs to see a logic LOW to HIGH transition ("rising edge") or a l ogic
HIGH to LOW transition ("falling edge") for the move to be started. Additionally, the
move parameters must be downloaded to the unit prior to the move using the relevent
relative move or absolute move software methods as described following. A move
already in progress will not be interrupted; therefore external triggering will not work
until the previous move has been completed.
In order to avoid unexpected moves being executed on start-u p, the trigg er input
settings cannot be persisted and will default to the input being disabled on power-up.
Even when input triggering is disabled, the state of the Trigger In input can be read at
any time by using the LLGetStatusBits software method to read the status register bit
1. This allows application software to use the Trigger In input as a general-purpose
digital input - see the
APTServer helpfile
for details on using the LLGetStatusBits
method and the status register.
