The throttle provides a proportional input to control the speed or torque of the motor. The Analog throttle interfaces function using a voltage on an interface pin (for example, TPOTC). The throttle can also be controlled digitally via CANBUS. This section describes digital control of the throttle; refer to Throttle for a more general discussion of throttle functions.
The Digital Throttle is also referred to as the Digital Pot. By default the Digital Throttle commands must be sent out every 50msec. There are several options in the Joystick Options register that control how the controller behaves when the commands start and stop The Digital throttle can be made to go to 0 when commands stop. There is also an option to stop the motor using quick stop. There is another option that forces the controller to go into Digital Throttle mode if it is not enabled when commands start. Only See Joystick Options for information on how to enable or disable quick stop after throttle commands cease to be sent. NOTE: Failband, Deadband, and Throttle Scale settings have no effect in this mode.
RAM Register 0x7A (Digital Throttle Pot)
|0-255||This is the equivalent to 0-5V analog throttle range|
The Value is an 8-bit number that equals the desired throttle setting. 0 is off and 1 or greater can start the motor moving. However, the motor may not shut off if used in mixed mode throttle control unless the manual throttle is set into the deadband region.
Set Digital throttle to 25% PWM:
Set RAM register 0x7A to 0x40 0x40 = 64 = 25% PWM
Digital Control (Buttons Register)
Use the Digital Control command to control motor direction or to implement a quick stop as well as other remote control features.
NOTE: All bits are set to 1 by default. All features are active low.
|0x01||Digital Forward||Run forward. Bit 1 must be set for this to work. NOTE: The throttle should be set to 0 before changing directions.|
|0x02||Digital Reverse||Run in reverse. Bit 0 must be set for this to work. NOTE: The throttle should be set to 0 before changing directions.|
|0x04||Reserved||Set to 1|
|0x08||Reserved||Set to 1|
|0x10||Quick Stop||Motor stops when set to zero. The stop diagnostic byte in RAM Register 0x12B will either indicate "Digital STOP" (0x03) or "Waiting for deadband" (0x0C). In either case the throttle(s) must be set to deadband or 0 to restart the motor. See Stop Diagnostics for more information on stop values.|
|0x20||Reverse||Set to 0 to reverse the motor if the controller is in analog or mixed throttle mode. NOTE: This bit has no effect if the reverse pin is active. Use bits 0 and 1 if in full digital throttle mode.|
|0x40||Indoor/Outdoor||Set to 0 for indoor mode. Set to 1 for outdoor mode.|
|0x80||Reserved||Set to 1|
Set motor to run reverse in indoor mode at 20% PWM:
Set EE register 0x57 to 0x07 Full digital control Set RAM register 0x7B to 0xBD Clear indoor/outdoor and digital reverse bits Set RAM register 0x7A to 0x33 0x33 = 51 = 20% PWM
Change direction slowly from reverse to 0 in 2 seconds. Forward to 50% PWM in 3 seconds:
Set RAM register 0x7A to 0x32 Decrement Wait 40msec Set RAM register 0x7A to 0x31 Note: Larger delays and bigger steps can be used Wait 40msec ... Set RAM register 0x7A to 0x00 Set RAM register 0x7B to 0xBE Clear indoor/outdoor and digital forward bits Set RAM register 0x7A to 0x01 0x80 = 128 = 50% PWM Wait 23msec Set RAM register 0x7A to 0x02 Wait 23msec ... Set RAM register 0x7A to 0x80 0x80 = 128 = 50% PWM
NOTE 1: If using CANBUS, the commands above can be done in using combined commands. See CANBUS Control Library