Delta RMC101 User Manual
Page 331
Ethernet 5.2
Communications
5-81
DL405
D4-
430
Cannot use Plots and the Spline Download Area.
D4-
440
Cannot use Plots.
D4-
450
Cannot use Plots.
Note:
The documentation below assumes the user to be familiar with DirectLogic PLC
programming, and instead focuses on how to initiate reads and writes to an RMC.
The standard method of initiating data transfers from a DirectLogic 205/405 PLC is to use the RX
and WX instructions. These instructions send data over raw Ethernet packets without using
TCP/IP at all. This results in better performance, but limits the PLC-to-PLC communication to a
single network (packets can not be routed to other networks or the Internet). Because IP is not
used, IP addresses cannot be used. In their place, each device has a unique Module ID ranging
from 1 to 90.
There is now a second method for initiating requests from the DL205/405 PLCs. This method has
the following advantages:
• It allows the user to select raw Ethernet, IPX, or IP as the transport layer.
• It uses the standard MAC and IP addresses instead of custom Module IDs.
However, this method has the following disadvantages:
• This method is new and therefore not documented in the current ECOM manual.
• This method requires allocating a 16-word V-memory block followed by the data to be read or
written. This requires a lot of manually copying data into buffers to be read or written and
introduces opportunity for PLC programming errors in setting up the 16-word header.
• This method does not have an implied remote (RMC) V-memory address and therefore would
require the user to program an additional header after the 16-word V-memory header.
Delta will continue to watch this method as it matures into being documented and used and listen to
customer requests, but at this time, it appears to make the integration more difficult to implement for
our customers with no tangible benefit.
Setting the RMC Module ID
Automationdirect.com ships a setup program called NetEdit with the ECOM manual. It can also
be downloaded from their supplier's site: http://www.hosteng.com. This program can be used to
set the Module ID of any ECOM or RMC module.
To set the RMC Module ID:
1. Ensure that your PC has TCP/IP installed.
2. Connect your PC and the RMC to the same network. Generally this involves plugging each into
the same Ethernet switch or hub.