Introduction; Syntax - Advantech ADAM 4000 Series User Manual

Command Set

4.1 Introduction

To avoid communication conflicts when several devices try to send data at
the same time, all actions are instigated by the host computer. The basic
form is a command/response protocol with the host initiating the sequence.
When modules are not transmitting they are in listen mode. The host issues
a command to a module with a specified address and waits a certain amount
of time for the module to respond. If no response arrives, a timeout aborts
the sequence and returns control to the host.
Changing ADAM's configuration might require the module to perform auto
calibration before changes can take effect. Especially when changing the
range, the module has to perform all stages of auto calibration that it also
performs when booted. When this process is under way, the module does
not respond to any other commands. The command set includes the exact
delays that might occur when 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 (hexadeci-
mal) that specifies the target module. The actual two character command
follows the address. Depending on the command, an optional data segment
follows the command string. An optional two character checksum may be
appended to the total string. Every commands is terminated by a carriage
return (cr).
ALL COMMANDS SHOULD BE ISSUED IN UPPERCASE
CHARACTERS!
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