Specifications

Diagnostic LEDs 33
DIAGNOSTIC LEDS
E271-2200, E271-2201, and E271-2202 Controllers
The E271-2200, E271-2201, and E271-2202 controllers have three diagnostic
LEDs. Following power on, the controllers perform their self-test. (ELODEV
displays the result of this test when loaded). After the self-test, a flashing green
LED indicates normal operation (except in Low Power Mode, see page 89). If a
fatal error was encountered, the yellow and red LED's flash an eight-bit error code
starting with the most significant bit, where yellow indicates a binary '0' and red a
binary '1'.
During normal operation, the yellow LED indicates controller/host communication
is in progress. For example, when the touchscreen is touched, the yellow LED
should light or flicker (may not be visible with bus controllers on fast PC's). If the
host does not remove the packet from the controller, the LED will stay lit.
If the yellow LED lights without a touch, the touchscreen or cabling may be
shorted. Disconnect the touchscreen cable from the controller and cycle power to
the controller to verify this condition.
A constant red LED indicates a warning error condition, such as improper
communication from the host. Suspect the baud rate or other communication
parameters.
E271-2210 Controller
The E271-2210 controller has one yellow diagnostic LED. Following power on,
the controller performs its self-test. (ELODEV displays the result of this test when
loaded). After the self-test, the LED flashes about 1.5 times a second, indicating
normal operation.
During normal operation, the LED also indicates controller/host communication is
in progress. For example, when the touchscreen is touched, the LED should light
or flicker, then return to the normal flash rate. If the host does not remove the
packet from the controller, the LED will stay lit.
If the LED stays lit without a touch, the touchscreen or cabling may be shorted.
Disconnect the touchscreen cable from the controller and cycle power to the
controller to verify this condition.
If the LED flashes about four times a second, a warning error condition is
indicated, such as improper communication from the host. Suspect the baud rate or
other communication parameters.