Advantech Data Acquisition Modules ADAM 4000, User Manual

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Command Set
4-2 ADAM 4000 Series User’s Manual
4.1 Introduction
In order to avoid communication conflicts among devices trying to send
data simultaneously, all the traffics are coordinated by the host
computer. This action is initiated by the host computer using a
command/response protocol.
When the modules are not transmitting, they are in listening mode. The
host issues a command to a module with a specified address and waits
for the module’s response. If there is no response, a timeout aborts the
sequence and returns the control to the host.
Changing ADAM’s configuration might require the module to perform
auto calibration before changes may take effect. This is the case when
the range is modified especially. The module has to perform all stages
of auto calibration which is also performed during the start up. When
the calibration process is underway, the module does not respond to any
other commands. The command set in the following pages includes the
exact delays that might occur as modules are reconfigured.
4.2 Syntax
[delimiter character][address][command][data][checksum] [carriage
return]
Every command begins with a delimiter character. There are four valid
characters: a dollar sign $, a pound sign #, a percentage sign % and an
at sign @.
The delimiter character is followed by a two-character address
(hexadecimal) that specifies the target module. The actual
two-character command follows by the address. Depending on the
command, an optional data segment may follows by a command string.
Furthermore, an optional two-character checksum may be appended to
the total string. Every command is terminated by a carriage return (cr).
ALL COMMANDS SHOULD BE ISSUED IN UPPERCASE
CHARACTERS!