An analog input is defined as a 0-5 volt signal. TPS, MAP, and EGO sensors are good examples of
analog output sensors. A speed input is defined as a frequency signal. When using a magnetic sensor as a
speed sensor, its output will be an AC sine wave. When using a Hall effect sensor, the output will be a 0-5
volt square wave.
One of the most useful functions of the GP I/O’s is trimming. Using a simple potentiometer
referenced to +5 volts and ground, it is possible to configure the inputs to trim the fuel and spark curves
based on the potentiometer knob position. These functions are quite easily configured in the WinTEC
software.
H.1.a. Available General Purpose Input (GPI) Functions :
Fuel Trim:
Trims the fuel curve by a set amount through the use of a potentiometer. See
Figure H.1.1
for
wiring diagram.
Ignition Advance Trim:
Trims the ignition advance angle by a set amount through the use of a
potentiometer. See
Figure H.1.1
for wiring diagram.
GPO Trim #1
and
#2 :
These functions allow the user to add or subtract up to 50 percent Duty Cycle from
the values established in the GPO table specified by the trim number. GPO Trim #1 only effects table 1,
GPO Trim #2 only effects table 2. See
Figure H.1.1
for wiring diagram.
A/C Idle Speed Increase:
On
TECgt
installations with an idle air control motor, this feature allows the
idle speed to be increased when the air conditioner is turned on. See
Figures H.1.2 and 3
for
recommended wiring.
Valet Switch:
When a speed input is used, the valet switch allows the user to set a speed limit on the
vehicle. The rev limiter will be activated when the desired speed is reached. See
Figure H.1.5
for wiring
diagram.
Nitrous Retard:
Provides a set amount of ignition timing retard when nitrous is activated. When used
with the Electromotive 4-stage timing retard module, the NOS Retard should be set to –30
o
(consult the 4-
Stage Nitrous Retard Instructions for wiring). When used with a potentiometer, the timing will be retarded
linearly from 0 to 30 degrees when a 0 to +5 volt signal is placed on a GP I/O input (channels 2-9). See
Figure H.1.4
for wiring diagram.
Speed Input:
Only available on GP I/O channel 2, the speed input allows the input of a frequency-based
signal. Many late-model vehicles use electric speedometers that use either Hall effect or reluctor triggering
mechanisms. These are both compatible with the
TECgt
speed input. Depending on the location of the
speed input trigger wheel, you must configure the software to calibrate the speed input signal to the actual
vehicle speed. See
Figure H.1.6
for typical sensor wiring.
Timed Advance:
When voltage (either 12v or 5v) is applied to the chosen GP I/O channel this function
allows the user to add or subtract up to 30 degrees of timing for up to 2 secs. in .05 sec. increments.
Timing will ramp up (advance) in the time specified (up to 2 seconds in .05 sec. increments) or down
(retard) when the channel is switched on. Switching the channel off will ramp the timing back to the values
in the Ignition Advance Table, the ramp back will happen in the specified time programmed by the user
within the software.
______________________________________________________________________________________
TECgt Manual Version 2.0
- Page 98 -
©2008 Electromotive, Inc.
