Horner APG XL4 OCS HE-ETN300 - Manual (Page 25)

SUP0740-07 CH.4
11/30/2009 Page 25 of 98 # 958
Figure 4.2 – I/O Configuration Download Warning
4.4.1 How to Prevent Losing Communication
Before using CsCAN over Ethernet to download a new I/O Configuration, to an OCS with an
Ethernet Module installed, the application programmer should:
1. Make sure the new I/O Configuration contains an Ethernet Module configuration.
2. Make sure the new Ethernet configuration will not change the IP Address.
Refer to Chapter 3 on how to check and/or correct Ethernet Module configuration and pay
particular attention to step 5 of the Ethernet Module configuration process in Section 3.1 (page
18 ), and to Section 3.2 (page 21 ), which explains in detail how the Ethernet Module obtains an IP
Address.
If the new Ethernet configuration specifies Static IP Address (Section 3.2.1 [page 21]), make sure
the IP Address parameter (Figure 3.5 [page 18]) matches Cscape’s Target IP Address (Figure
4.1).
If the new Ethernet configuration specifies Static IP Address with CAN ID (Section 3.2.2 [page
21]), make sure the IP Address, which will be built from the combination of the IP Address
parameter (Figure 3.5 [page 18]) and the OCS/RCS CAN Network ID, matches Cscape’s Target
IP Address (Figure 4.1).
If the new Ethernet configuration specifies IP Address from OCS Register (Section 3.2.3 [page
22]), make sure the OCS register indicated by the IP Addr Register parameter (Figure 3.5 [page
18]) contains an IP Address, and that it matches Cscape’s Target IP Address (Figure 4.1). If
necessary, use Cscape’s Data Watch facility to set the OCS register to the correct IP Address
before downloading.
4.4.2 How to Recover from Lost Communication
If the Ethernet Module’s IP Address changes as a result of using CsCAN over Ethernet to
download a new user program, activity will halt at the end of the I/O Configuration download, and
communication between Cscape and the target OCS will be lost. Then, after several seconds,
Cscape will display a Communication Timeout error.
If this happens, it is possible to recover Cscape communication with the target OCS, as follows:
1. Referring to Chapter 3 (especially Section 3.2 [page 21]) and to Section 4.4.1, determine
the Ethernet Module’s new IP Address, by using Cscape to re-examine the I/O
Configuration just downloaded.
2. Referring to Figure 4.1, change Cscape’s Target IP Address to match the Ethernet
Module’s new IP Address.
3. Try performing the download again.