5.
Technical Overview
5.1.
Pin Usage
All pins that are not in use on the EDBG, will be tri-stated. This is done to avoid signal contention. Note
that the tri-stating of serial communication lines and external interference could lead to unintended data to
be received by the target MCU.
5.2.
Power Consumption
During enumeration, the EDBG reports a current consumption of 500mA, and must therefore be
connected to a USB host that is capable of supplying this. It is impossible to predict the amount of current
required by the setup, since the EDBG is a part of a flexible evaluation kit.
The EDBG alone consumes approximately 100mA during usage. When the EDBG does not detect a
VBUS voltage, but is otherwise powered (for example through the Xplained Pro PWR header), the EDBG
will go into sleep to minimize power consumption. The power consumption during sleep mode will vary
with the design, but should be well below 1mA.
5.3.
LED Control
The EDBG controls two LEDs; the power LED and the status LED. The power LED is on by default when
the kit is powered, but can be disabled by the EDBG to lower the power consumption of the kit. The
status LED is turned on when a host computer opens a connection to the USB interface. During
communication activity the status LED will flash.
If the EDBG enters bootloader mode, both the status LED and the power LED will flash simultaneously.
When a firmware upgrade is in progress the LEDs will blink alternately.
The behavior of the EDBG LEDs is summarized in the table below.
Table 5-1. EDBG LED Control
Operation mode
Power LED
Status LED
Normal operation
Power LED is lit when power is
applied to the board.
Activity indicator, LED flashes every time
something happens on the EDBG.
Bootloader mode
(idle)
The power LED and the status LED blinks simultaneously.
Bootloader mode
(firmware upgrade)
The power LED and the status LED blinks in an alternating pattern.
Atmel EDBG [USER GUIDE]
Atmel-42096C-EDBG_User Guide-10/2016
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