Alien Technology ALR-8780, Interface Manual

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C
HAPTER
4 A
LIEN
R
EADER
P
ROTOCOL
R
EADER
I
NTERFACE
G
UIDE
D
OC
. C
ONTROL
# 8101938-000 R
EV
05
49
ExternalInput Examples
Command
Response >get ExternalInput
ExternalInput = 2 (i.e., binary "10")
ExternalOutput
9800 | 9780 | 8780 | 9640 | 9774
The reader controls four external output pins, which can subsequently be used to
control external devices such a doors/gates, security lights, etc. Please refer to
the Hardware Setup Guide for pinout diagrams.
With this command you can get or set the external output pin states. The single
parameter/return value is an integer bitmap representing the states of the
external output pins.
Bit 0 represents the state of output #1, bit 1 represents the state of
output #2, etc.
For example, to set pin 1 to high and pin 0 on low, use the bitmap of
2
decimal
, which translates to 10
binary
.
The ALR-9640's output states are inverted, as compared to the other
fixed readers. This can be rectified by using the InvertExternalOutput
command.
ExternalOutput Examples
Command
Response >set ExternalOutput = 2
ExternalOutput = 2
Command
Response >get ExternalOutput
ExternalOutput = 2
InitExternalOutput
9800 | 9780 | 8780 | 9640 | 9774
When the reader is powered up, it sets the external output pins to states defined
by the InitExternalOutput attribute. This gives you the flexibility to choose which
output pins should default to high, and which output pins should default to low – a
very important consideration if there are mechanical devices controlled by the
readers I/O port.
With this command you can get or set the initial external output pin states. The
single parameter/return value is an integer bitmap representing the states of the
external output pins during and after a startup.
Bit 0 represents the desired state of output #1, bit 1 represents the
desired state of output #2, etc.
For example, to set pin 1 to high and pin 0 on low, use the bitmap of
2
decimal
, which translates to 0010
binary
.
Changes made with this command take effect during the next reboot.
The bitmap that you specify is applied directly to the outputs upon
startup, without any inversion that may have been set with
InvertExternalOutput.