Delta MMC120 - Manual (Page 107)

107
CONFIGURATION Word
Default: 0000
Eleven bits of this 16-bit word control the configuration of the module. Bit 1 is the MSB;
bit 16 is the LSB.
Click here for the CONFIG Word Bit Map
Bits 1 - 4 - Transducer Type bits
Set these bits all to 0 if the transducer is start-stop.
If the transducer is gated, set the bits so the value of these four bits equals the number of
recirculations the gated transducer is set to (bit 1 = 8, bit 2 = 4, bit 3 = 2, and bit 4 = 1).
For example, if the transducer is set to one recirculation, bit 4 should be set. If the
transducer is set to 10 recirculations bits 1 and 3 should be set, and if it is set for 15
recirculations, all four bits should be set to 1.
When a transducer is set for multiple recirculations, there is a small time delay between
those recirculations. During this time the counter on the motion controller continues to
count, resulting in "extra" counts which are added to the TRANSDUCER COUNTS .
These extra counts use some of the 65535 maximum counts that are available, reducing
the maximum stroke the module can control to 65535 minus the "extra" counts. To
correct for this effect the module calculates the "extra" counts based on the number of
transducer recirculations and subtracts them from the transducer count. If the value of
these bits and the transducer recirculations agree, the transducer count will be slightly
positive when the transducer is at its minimum position.
If you are using a gated transducer and want resolution better than 0.001 inches, we
suggest using 10 recirculations and setting bits 1 and 3. This will give 0.0001-inch
resolution with a stroke of about 6.5 inches.
Bit 9 – Falling edge Transducer bit
When this bit is set the Transducer interface hardware is configured to respond to the
falling edge of the pulses on a start/stop type transducer. If any of the transducer type
bits (1 through 4) are set, this bit is ignored.
Bit 10 - Reverse Drive Mode bit
When this bit is set the polarity of the axis’s output voltage is reversed. This bit is useful
when you are connected to two drives which do not have differential or isolated inputs,
and you need one to extend with positive drive and the other to extend with negative
drive. (If the drives have differential or isolated inputs, you can just reverse the
connections to the drive that must extend with negative drive.) When this bit is set,
transducer counts will DECREASE with positive drive.
Warning: This bit must be set properly when the Set Parameters command is issued.
Bit 11 - Absolute Mode bit