About Embedded Module Leds; Embedded Module Reset - Digi Connect EM DC-EM02T-JT Hardware Reference Manual

Programming considerations

About embedded module LEDs

LED
Green
(above yellow
LED)
Green
(the one above
the red LED)
Yellow
Red

Embedded Module Reset

Hard Reset
The embedded modules support a hardware reset on pin 10 of the 12-pin header. The unit will be
forced into a hard reset if this pin is pulled low. When used with the development board, this pin is
wired to reset button SW5, which means it acts as a hard reset button.
Soft Reset
NET+OS provides an internal facility to enact a soft reset, but it is the responsibility of a specific
implementation to choose a reasonable trigger to invoke it. One choice is to use a GPIO pin as a signal
to trigger a soft reset. The embedded modules have one GPIO pin (PORTC5) which is not normally
assigned to any other task named "/INIT." It is an ideal candidate for use as a signal for soft reset.
The signal is wired to the push button on the module (next to the LEDs), and is pulled high unless the
button is pushed.
The "naresetapp" sample application demonstrates a simple mechanism for monitoring a GPIO pin
and then initiating a soft reset when the pin achieves a particular value.
Digi Connect EM and Digi Connect Wi-EM Hardware Reference
Embedded module LED description
This LED is wired to the network hardware and provides an indication of link
status.
This LED is software programmable and is wired to processor GPIO register bit
PORTC4 and wired to be lit when low.
This LED is software programmable, wired to processor GPIO register bit
PORTC2,
and wired to be lit when low.
This LED is software programmable, wired to processor GPIO register bit
PORTC6,
and wired to be lit when low. The default is that this LED indicates power
(and is therefore always on).
Reset characteristics
Characteristic
Delay
Threshold
Minimum hold time
Description
Specification
200 milliseconds (typical)
2.93 V
1 microsecond pulse
Embedded Module Reset
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