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2.6 Usage of GPIOs
The reader provides four general purpose I/Os that can be configured individually. These I/Os can be
read and written by commands.
Please consider, that the GPIOs have limited current source and sink capability of max. 25mA. An
overcharge of GPIO-pins can damage the module!
2.7 Asynchronous Reset
In usual operating environments, the reset pin can be left floating. For an asynchronous hardware
reset pull the reset pin to a logic low level. The reader continues operation as soon as the reset pin is
released.
2.8 Power Supply
A power supply of 3.3V – 5V must be applied between the VCC and GND pins. Please make sure that
the power supply provides a current capability of at least 100mA.
Please note: The current consumption can be significantly increased if GPIOs and/or SAM module are
used. The total current consumption may not exceed 150mA.
2.9 Hard Power Down
The reader supports a hardware power down feature which enables the user to turn off the entire
reader. Hard power down mode is entered by pulling the PWRDWN
off the internal voltage regulator.
Please note: Maximum power saving can be achieved by entering this mode, but this also means that
the reader needs the boot time until it is available again.
2.10 SAM
The reader supports connection of ISO7816 compatible SAM cards. The lines SAM_IO, SAM_CLK,
SAM_RST, VSAM and GND have to be connected as follows:
SAM card
C1
C5
C2
C6
C3
C7
C4
C8
Elatec GmbH
¯¯¯¯¯¯¯ pin to low; this results in turning
Pad
Line
C1
VSAM
C2
SAM_RST
C3
SAM_CLK
C4
Leave open
C5
GND
C6
Leave open
C7
SAM_IO
C8
Leave open
Page 12 of 61
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