Rs 232 C Serial Interface; Configuration; Instruction Syntax; Overview Of The Namur-Instructions - IKA IKAMAG RET control-visc C Betriebsanleitung

14.1 Serial RS 232 C interface
14.1.1

Configuration

The unit can be controlled from an external PC (using the dedi-
cated software labworldsoft) via the RS 232 C serial interface
fitted to the unit.
To increase safety when controlling the RET control-visc/C
from a PC, enable the watchdog function for monitoring
the continuous serial data flow. (see section 14.1.4)
• The functions of the interface lines between laboratory
instrument and automation system are selected from the spe-
cified signals of the EIA-standard RS 232 C, corresponding
with DIN 66 020 Part 1. The allotment of the bushing can be
taken from illustration.
• For the electrical properties of the interface lines and for the
allotment of the signal status, standard RS 232 C, correspon-
ding with DIN 66 259 Part 1 applies.
• Transmission method:
• Mode of transmission:
• Character format:
• Transmission speed:
• Data flow control:
RTS: (pin 7) LOW (positive tension)
RTS: (pin 7) HIGH (negative tension)
CTS: (pin 8) LOW (positive tension)
CTS: (pin 8) HIGH (negative tension)
• Access method:
RETCV_0107
Asynchronous signal transmis
sion in start-stop-operation.
Fully Duplex.
Character imaging acc. to data
format DIN 66 022 for start-
stop-operation. 1 start bit;
7 character bits; 1 parity bit
[straight (even]); 1 stop bit
9600 bit/s
Hardware handshake RTS/CTS
/ computer may send
/ computer may not send
/ computer recipient
/ computer not recipient
Data communication from
laboratory instrument to com-
puter is only possible on
demand of the computer
14.1.2

Instruction syntax

Here applies the following:
• The instructions are generally sent from the processor
(master) to the laboratory instrument (slave).
• The laboratory instrument exclusively sends on demand of
the processor. Even error codes cannot be spontaneously
communicated from the laboratory instrument to the proces-
sor (automatic system)
• The instructions are transmitted in capital letters.
• Instructions and parameters as well as subsequent parame-
ters are separated by at least o n e blank. (Code: hex 0x20)
• Each individual instruction including parameters and data as
well as each reply are terminated with CR LF (Code: hex 0x0D
and 0x0A) and have a maximum lenght of 80 characters.
• The decimal separator in a floating point number is the point.
The above statements largely correspond with the recommen-
dations of the NAMUR-Association. (NAMUR-recommendati-
ons for the design of electric plug connections for the analog
and digital signal transmission to laboratory - MSR individual
units. Rev. 1.1)
14.1.3

Overview of the NAMUR-instructions

Abbreviations:
X,y = numbering parameter (integer number)
m = variable value, integer
n = value of variable, floating point number
X = 1 Pt100 or Pt1000 medium temperature
X = 2 heating plate temperature
X = 3 heating plate - safety temperature
X = 4 speed
X = 5 viscosity trend
X = 7 Pt1000 heat transfer medium temperature
(Code: hex 0x2E)
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