TTL Inputs and Outputs
Main Encoder Inputs
The main encoder inputs can be configured for quadrature (default) or pulse and direction inputs. This
configuration is set through the CE command. The encoder connections are found on the HD D-sub Encoder
connectors and are labeled MA+, MA-, MB+, MB-. The '-' (negative) inputs are the differential inputs to the
encoder inputs; if the encoder is a single ended 5V encoder, then the negative input should be left floating. If the
encoder is a single ended and outputs a 0-12V signal then the negative input should be tied to the 5V line on the
DMC.
When the encoders are setup as step and direction inputs the MA channel will be the step or pulse input, and the
MB channel will be the direction input.
The encoder inputs can be ordered with 120Ohm termination resistors installed. See TRES – Encoder Termination
Resistors in the Appendix for more information.
Electrical Specifications
Maximum Voltage
12 VDC
Minimum Voltage
-12 VDC
Maximum Frequency (Quadrature) 15 MHz
'+' inputs are internally pulled-up to 5V through a 4.7 kΩ resistor
'-' inputs are internally biased to ~1.3V
pulled up to 5V through a 7.1 kΩ resistor
pulled down to GND through a 2.5kΩ resistor
The Auxiliary Encoder Inputs
The auxiliary encoder inputs can be used for general use. For each axis, the controller has one auxiliary encoder
and each auxiliary encoder consists of two inputs, channel A and channel B. The auxiliary encoder inputs are
mapped to the inputs 81-96. The Aux encoder inputs are not available for any axis that is configured for step and
direction outputs (stepper).
Each input from the auxiliary encoder is a differential line receiver and can accept voltage levels between ± 12
volts. The inputs have been configured to accept TTL level signals. To connect TTL signals, simply connect the
Chapter 3 Connecting Hardware ▫ 40
DMC-40x0 User Manual
Figure 3.7: 500mA Sourcing wiring diagram for Bank 1, DO[16:9]