GSE 60 SERIES Technical Reference Manual page 469

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which is used to read the current encoder count value, as determined by this function.
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scale factor for the encoder count value. This allows the input signal to be converted to a value with meaningful
units such as Feet, Meters, Inches, Degrees of rotations, etc.
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every time the encoder signal changes. If P863 is not 'None', then the value provided by P50 will be the encoder
count value multiplied by the scaling factor specified by P863 and the number of decimal places used when
displaying and transmitting P50 is specified by P864. Otherwise 'QdDc2's P50 will show zero decimal places.
Q D
UADRATURE
The 2 wire quadrature decode feature processes a pair of signals output
by an encoder. It can be used to determine the position of a device that
rotates or moves back and forth since it simultaneously senses both
distance and direction of travel of the device.
Two sequential channels are required on the Programmable I/O connector
in order to use the two wire quadrature decode feature. Therefore this
function cannot be assigned to channel 8.
The setup parameters that pertain to the 'QdDc2' selection are:
P852: "Pnam": Allows a name to be assigned to I/O parameter 50
P863: "SFac": Specifies which parameter is intended to provide a
To specify a scaling factor, first allocate a Var for this purpose, then
key in 80.X [ENTER] where 'X' is the Var number to be used.
(Although we allow parameters other than Vars to be used as scaling
factors, most applications would logically use only Vars as scale
factors.) Then, in the weigh mode, enter the value of the pre-scale
value into the specified Var.
P864: "# DP": This parameter is only available if P863 is not set to
'None'. It specifies the number of decimal places shown when viewing
or transmitting the scaled encoder count. When P864 is not available
(due to P863 = 'None'), zero decimal places are used for displaying
the encoder count value.
Please note that the next channel of the Programmable I/O port will
automatically be set to 'QdDc2' and is not changeable. There are no
setup or weigh mode parameters associated with the second channel.
The 'weigh mode' parameter available for 'QdDc2' is:
P50: The current encoder count value. This parameter is updated
A new value may be entered at any point. Any subsequent pulses
input from the encoder will increment or decrement the new value
accordingly.
The encoder count value is a 16 bit counter and thus is limited to a
maximum value of +32767 and a minimum value of -32768. If the
encoder output is allowed to increment or decrement past this value it
will wrap around to the other extreme value and continue from there.
When the 660 is first powered up and when setup mode changes are
saved the value of this parameter is zeroed out.
Programmable Digital I/O 12-23
, 2 W
ECODE IRE
60 Series Technical Reference Manual
(F 8)
UNCTION