PROTEUS
OMNTEC
Mfg., Inc., 2420 Pond Road, Ronkonkoma, NY 11779
Phone (631) 981-2001 Fax (631) 981-2007 www.OMNTEC.com
File Name: DE00014 DE00015 DE00020-10 rev2045.docx Page 5 of 71 Rev Date: 10-15-2021
Serial Interface Manual
OEL8000III Series Models K/X
2.3 ETHERNET INTERFACE
The Ethernet interface is located on the left (K) or bottom-left (X) of the controller beside the RS-232 port.
3.0 CHARACTER FORMAT
The system receives and sends characters via all interfaces in an ASCII format. Characters are not echoed when
received, and transmitted characters must not be echoed back to the system.
3.1 COMMAND MESSAGE FORMAT
All command and response messages are configured in a format which includes a control character(s), a function
code and a data field. The control characters are described in this section while the function codes and data field
messages are described in subsequent sections.
The system responds to a command message that has the following configuration:
SOH | Format Char | Command Code | Data Field
SOH
is a control-A character (ASCII 01). Start of string.
The
Format Character
(I, i, S, s) determines the type of command and response. A upper-case format character
will return a response in display format. A lower-case format character will return a response in computer format.
“I, i” = information response. “S, s” = set command.
The
Command Code
is a three or six character command code which the system interprets to determine the type of
action to take. System command codes and response messages are defined in subsequent sections.
The
Data Field
contains information necessary to perform the selected function (such as tank number and setup
information).
4.0 RESPONSE MESSAGE FORMAT
There are two types of response message formats: computer (or compressed data format) and display format. Each
format uses a different format character.
If the system receives a command message string containing a function code that it does not recognize, it will
respond with a <SOH>9999FF1B<ETX>. The "9999" indicates that the system has not understood the command,
while the "FF1B" is the appropriate checksum for the preceding <SOH>9999 string.
