Curtis 1234E - Potentiometer Inputs

Curtis 1232E/34E/36E/38E & 1232SE/34SE/36SE Manual, os 30
111
24 NOVEMBER 2015
Set_DigOut(DigOut6)
will set Digital Output 6 On (active). VCL can monitor the present value of
a digital output driver: the bit variable Digx_Output (where “x” is the digital
output channel number) is automatically filled with the present value of the
driver output (On or O).
It is important to note that all outputs are active Low. With 100% PWM
or an output of “On,” the FET or transistor will be pulling hard to ground. A
DVM on the output will measure near 0 volts.
Potentiometer Inputs
ese controllers have two potentiometer inputs, which are typically used for
throttle and brake. Many features (mapping, acceleration rates, etc.) are built in
as 1313/1314 programmer parameters. Still, there are times that these potenti-
ometer inputs may be needed for other functions such as steering angle or height
sensing, or simply as data inputs. e standard way to input pot information is
to set the parameter rottle Type (or Brake Type) to an appropriate value of
1–4 as shown on pages 13–16. When set to a value of 1–4, the resulting signal
chain can operate without the use of any VCL.
However, if an OEM wishes to control the throttle (or brake) signal chain
in VCL or use the throttle (or brake) inputs for signals that are not throttle
(or brake) signals, then the parameter rottle Type (or Brake Type) should
be set to a value of 5 (page 17). Setting the parameter rottle Type (or Brake
Type) to a value of 5 changes the routing of the appropriate signal chain (either
throttle or brake) and allows the VCL programmer access to the rottle Pot
(or Brake Pot) output variables; see Figure 15 (page 114).
Typically the Setup_Pot() function is executed at the beginning of a VCL
program to define the potentiometer input connection as
THREE_WIRE (uses Pot
High and Pot Low connections),
TWO_WIRE (variable resistor, or rheostat, uses
Pot Low but no connection to Pot High), or
ONE_WIRE (a voltage input, no
connection to either Pot High or Pot Low).
THREE_WIRE potentiometer con-
nections are the same as the 3-wire potentiometer connections shown on page 15
for a rottle Type 2. TWO_WIRE potentiometer connections are the same as
the 2-wire potentiometer connections shown on page 14 for a rottle Type 1.
ONE_WIRE potentiometer connections are the same as the Voltage Source or
Current Source connections shown on page 15 for a rottle Type 2.
Note that the Setup_Pot() function will only work (and is only needed)
if the corresponding Type is set to 5 (rottle Type = 5 or Brake Type = 5).
Setup_Pot(THROTTLE_POT,THREE_WIRE)
will set up the throttle pot input for wiring using all three connections (pins
15, 16, 18).
To set up the brake pot input for use in VCL, use the Brake_Pot constant
in place of the ottle_Pot constant in the Setup_Pot function.
Setup_Pot(BRAKE_POT,TWO_WIRE)
will set up the brake pot input for wiring using two connections (pins 17, 18).
8 — VCL