MoTeC SDC3 - Manual (Page 8)

MoTeC SDC3 6 Functionality
Throttle Calibration
The throttle position sensor input can be calibrated using a table to convert voltage to throttle position. This allows
non-linear calibration of throttle position to more closely model the change in torque vs. throttle butterfly angle.
The SDC Manager configuration program allows throttle input voltages to be read directly from the SDC3 in order
to perform 0% and 100% calibrations.
For information on calibrating the throttle input, see Setup | Input in the SDC Manager section.
Communications
The SDC3 communicates on the factory CAN bus at 500kBit/sec.
PC CAN Connection
A CAN interface to the SDC3 is provided using a MoTeC OEM Communications cable that plugs into the SDC3
board. This cable also provides the power required if the MoTeC CAN cable is used to interface with a PC.
The MoTeC UTC (USB To CAN) adaptor or the MoTeC CAN cable can be used to connect the PC to the CAN
bus.
Vehicle Communications
The SDC3 communicates with the ABS module, Body Integrated unit, ECU, Yaw/G sensor and Steering Angle
Sensor over the CAN bus using the factory wiring loom.
The SDC3 receives wheel speeds, brake status, yaw, lateral G, longitudinal G, steering angle, ABS status,
throttle position and manifold pressure on the CAN bus.
MoTeC ADL/M800 Communications
The SDC3 transmits CAN messages at 50Hz containing information about all input and output functions, such as
speed readings, diff currents, duty cycles etc.
The SDC3 transmits CAN messages at 25Hz containing diagnostic information such as fault flags, firmware
versions etc.
The ADL can be configured to receive all these channels and an M800 ECU can be configured to receive a
subset of the channels.
To configure an ADL to receive SDC3 messages, use the ‘SDC3’ and ‘SDC3 Diagnostics’ communications
templates included with Dash Manager.
See Appendix E – ECU Communications for information on configuring an M800 ECU to receive SDC3
messages.
The transmission of CAN messages can be disabled. This feature may be used to prevent reverse engineering of
user control modes.
Miscellaneous functions
Diff Temperature Override
The diff temperature override functionality allows a specified control mode to be used if the rear diff overheats.
If this functionality is enabled, the current user control mode (1-4) is overridden with the configured override
mode (0%, 100% or one of the 4 user modes) while the rear diff temperature input is active. The diff temperature
override does not occur if the thumbwheel is in the full lock or open lock positions.
To prevent rapid transitions between control modes when the diff heats or cools, the diff temperature input must
be stable in a new state (high or low) for 2 seconds before the input is considered to have changed.