Adcon A440, Technical Reference Manual

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Software
4.3. Controlling the Unit
The unit under test can be controlled by means of the special adapter box A720PS
that supplies the unit on one hand, and performs the RS-485 to RS-232 signal con-
version on another hand. The serial output of the box can be connected to a PC (e.g.
a laptop) by means of a null modem cable. In order to switch the unit to various
modes of operations, a simple communications terminal program will suffice (e.g.
Terminal or Hyperterminal in Windows, or tip/cu under Unix). The terminal program
must be configured as follows:
• 19200 Baud
• 8 Data Bits
• No Parity
• 1 Stop Bit
• Force LF after CR
4.3.1. Serial Communication Protocol
This protocol is based on a master sending commands and a node answering; the
whole communication is conducted in plain ASCII, as strings. When exchanging
numbers, they are represented in decimal format. All commands are terminated with
a CR/LF combination. All responses (answers) are terminated with the
# character.
4.3.2. General Format of a Command
The commands have the following format:
ID Command Param1 Param2 ... ParamN
•
ID
is the destination device. If you include an ID as part of a command, the
node checks whether
ID=ownID
. If it does, the node executes the command
on itself. If the ID is not the node’s ID, the node executes the command on a
remote device, if such an ID exists. If the ID is missing, this implies that the
command is addressed locally.
Note: Not all the commands can be relayed remotely.
•
Command
is the command proper, which can be composed of a variable string
of characters (for example,
SLOT
). Each node can implement a set of com-
mands depending on the functionality of the node itself. However, as a mini-
mum requirement, a node recognizes the
CMDS
command, which returns a list
with the commands recognized by the node.
•
Param1 Param2 ... ParamN
represent the parameters, which are com-
mand dependent. If you type no parameters when you issue a command, it is
the equivalent of querying for information (the
GET version of a command). If
you type parameters, you are issuing the SET version of a command and are
setting the command to the parameters you typed.