Omron CJ - REFERENCE MANUAL 07-2009

33
FINS Command and Response Frames Section 3-3
3-3-3 Individual Items in Command/Response Frames
ICF
The ICF (Information Control Field) is configured as shown in the following
diagram.
Note Set bits 01 to 05 to 0 when sending a FINS command. Do not access these
bits when receiving a FINS response.
RSV
RSV (Reserved) is always 00 hex. These bits are used by the system. Do not
access them in the response.
GCT
When communicating across up to 8 network layers with CPU Unit with unit
version 2.0 or later, set the GCT (Gateway Count: Number of Bridges Passed
Through) to 07 hex when sending a FINS command. Otherwise, set the GCT
to 02 hex (see note) when sending. When receiving a FINS response, GCT is
decremented one for each bridge (network) that is passed through and the
resulting value is received. This value is for system use; do not access it.
Note For a CS/CJ-series CPU Unit with unit version 2.0 or later, CP-series CPU Unit,
or NSJ Controller, CX-Programmer version 4.0 or higher can be used to set rout-
ing tables that start the GCT at 07 hex. For a CS/CJ-series CPU Unit with unit
version 3.0 or later, CX-Programmer (CX-Net) Ver. 5.0 or higher can be used to
set routing tables that start the GCT at either 07 Hex or 02 Hex. For details, refer
to 1-4-2 Communications through a Maximum of 8 Network Levels in the CS
Series PLC Operation Manual or the CJ Series PLC Operation Manual.
DNA
Destination network address. Specify within the following ranges (hex).
00: Local network
01 to 7F: Remote network address (decimal: 1 to 127)
DA1
Destination node address. Specify within the following ranges (hex).
00: Internal communications in PLC
01 to 20: Node address in Controller Link Network (1 to 32 decimal)
01 to FE: Ethernet (1 to 254 decimal,
for Ethernet Units with model numbers ending in ETN21)
FF: Broadcast transmission
DA2
Destination unit address. Specify within the following ranges (hex).
00: CPU Unit
FE: Controller Link Unit or Ethernet Unit connected to network
10 to 1F: CPU Bus Unit
E1: Inner Board
SNA
Source network address. Specify within the following ranges (hex).
00: Local network
01 to 7F: Remote network (1 to 127 decimal)
Bit
Always 0. (See note.)
Response (0: Required; 1: Not required)
Data classification (0: Command; 1: Response)
Bridges (0: Not used; 1: Used)
Always 1.