Omron E5ZD, Руководство по эксплуатации

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3-1 Overview
Basic operating parameters are designated via switches on the board as de-
scribed in Section 2. Other parameters are then designated via communications
from the host computer. These parameters are input in groups which are stored
in the memory banks, and can be changed, as a set, by designating a new
memory bank.
Once all of the required operating parameters have been input, control outputs
and alarm outputs are initiated according to these parameters and their relation-
ship to the temperatures received at the temperature inputs.
Alarms include general error alarms to indicate errors in E5ZD operation, as well
as HB and HS alarms, which can be generated by using a Current Transformer
for the heating device.
3-2 Communications
Communications is the most important aspect of E5ZD operation. Communica-
tions can be used for everything, from setting and reading parameters to central-
ized data management. The basic communications procedure and protocol are
described here. The actual commands used in communications are described in
Section 4 Command Set .
3-2-1 Communications Procedure
All communications are initiated by the host computer by sending an command
block to the E5ZD. The E5ZD then sends a response block back to establish
conversation-type communications, i.e., each time a block is transmitted, the
transmission right is also transferred. The host computer must be set up to re-
ceive the responses sent by the E5ZD. If the host computer does not receive any
response, the reception buffer on the host computer may overflow. When you
have turned off and on the E5ZD, do not fail to initialize the reception buffer be-
fore you send a command from the host computer, otherwise smooth data re-
ception cannot be expected.
Host computer/E5ZD communications can be illustrated as follows:
Host computer
E5ZD
Command block
transfer
Response block
transfer
Command block
transfer
Response block
transfer
Communications
Section 3-2