Alien Technology ALR-8780, Interface Manual, Page: 35 / 104

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HAPTER
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LIEN
R
EADER
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ROTOCOL
R
EADER
I
NTERFACE
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UIDE
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OC
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ONTROL
# 8101938-000 R
EV
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Overview of Commands
There are two distinct categories of reader activities: those initiated by the host
(Interactive Mode), and those initiated by the reader itself (Autonomous Mode).
I
NTERACTIVE
M
ODE
Interactive Mode activities are initiated by a program or user who issues
commands to the reader from a separate host computer. The host always
initiates the transaction with a request, and the reader responds with an
immediate reply. The host should wait for a reply before initiating another
command.
Interactive commands are used to configure and operate the reader, as well as to
interrogate tags and retrieve the stored TagList on demand.
A
UTONOMOUS
M
ODE
Autonomous Mode activities instruct the reader to perform certain tasks without
outside intervention, according to conditions set by the programmer.
These commands typically tell the reader to read tags based on trigger events
(external digital inputs or internal timers) and then send notification messages to
a host system, depending on various TagList-based triggers. For example, the
reader can be instructed to search the field until it sees a tag, then to read the
new tag and e-mail the event to a specified e-mail address.
Command Format
All commands between the host system and the reader are human readable,
ASCII text-based messages. For example, a command to set the name of the
reader using the "set ReaderName" command takes the form:
Alien >set ReaderName = My Alien Reader[CR][LF]
All commands to the reader are single-line ASCII strings, terminated by a
carriage-return / line-feed pair, written as [CR][LF]. The [CR] character is ASCII
code 0x0D, while the [LF] character is ASCII code 0x0A. These characters are
sometimes written as "\r" and "\n" respectively.
All responses from the reader are either single-line or multi-line ASCII strings,
terminated by [CR][LF][0], where [0] is ASCII code 0x00. When a responses is
comprised of multiple text lines, each line is separated by a single [CR][LF]
sequence.
An example of a command and single-line response is:
Alien >get ReaderName[CR][LF]
ReaderName = Alien Reader[CR][LF][0]
An example of a command and multi-line response is:
Alien >get ReaderVersion[CR][LF]
Ent. SW Rev: 03.00.10 : Jun 08 2004 : 10:54:30[CR][LF]
Country Code: 01, Reader Type: 03, Firmware Rev: 2.1.4[CR][LF][0]
Commands are not case sensitive:
“ set readername ” is equivalent to “ sET ReADerNaME ”.