302; Protocol Definitions; Used Terms; Rs-232 - WEG CFW-09 User Manual

CHAPTER 8 - CFW-09 OPTIONS AND ACCESSORIES

8.13.2.2 RS-232

8.13.3 Protocol Definitions

8.13.3.1 Used Terms

302

Other ASCII characters used in protocol
CODE
0
1
2
3
4
5
6
7
8
9
=
STX
ETX
EOT
ENQ
ACK
NAK
Table 8.21 - ASCII characters used in protocol
The connection between the network participants is performed through a pair
of wires. The signal levels are according to STANDARD EIA RS-485 with
differential receivers and transmitters. Expansion boards of the types EBA.01,
EBA.02 or EBB.01 (refer to items 8.1.1 and 8.1.2).
When the master is fitted with only a serial interface - standard RS-232, you
must apply a level conversion module from RS-232 to RS-485.
In this case we have the connection of a master to an inverter (point-to-point).
Data can be changed in a bi-directional way, but not simultaneous (HALF
DUPLEX).
The logical levels meet STANDARD EIA RS-232C that determines the use of
balanced signals.
In this case, one wire is used for transmission (TX), one for reception (RX) and
one for return (0 V) .This configuration is a three-wire economy model. (Refer
to item 8.6)
This item describes the protocol used for serial communication.
Parameters: are those existing in the inverters whose visualization or
alteration is possible through the HMI interface.
Variables: are values that have specific inverter functions and that can
be read and, in some cases, modified by the master.
Basic variables: are those that can be accessed only through the serial
interface.
ASCII
DEC HEX
48 30
49 31
50 32
51 33
52 34
53 35
54 36
55 37
56 38
57 39
61 3D
02 02
03 03
04 04
05 05
06 06
21 15