Rockwell Automation Allen-Bradley AADvance T9110, Solutions Handbook

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60 Rockwell Automation Publication ICSTT-RM447M-EN-P - July 2019
Chapter 3 Controller Functionality
After having set up the IP address data in the controller, you can configure the
AADvance Workbench to find the controller on the network.
Recovery Mode Recovery Mode is a shutdown mode and uses a base level firmware. It is
entered automatically when a critical firmware failure occurs or it can be
entered manually by pressing the processor Fault Reset button immediately
after the module has booted up. The Recovery Mode is also used when you
want to download a new firmware upgrade.
As an alternative firmware version it allows the following maintenance
activities:
• Update the firmware using the ControlFLASH utility
• Program the processor IP Address with the AADvance Discover utility
• Extract diagnostic information
In Recovery Mode the Ready, Run, Force and Aux LEDs go Amber and the
Healthy and System Healthy LEDs stay Green. The System Healthy and
Healthy LEDs could go Red if a fault is detected while in the Recovery Mode.
Differential Services
(DiffServ) Differentiated services (DiffServ) gives a simple and coarse method to classify
the services of different applications, and thus specify the priority of IP traffic.
DiffServ is useful to make sure that high priority services are not delayed (or
less delayed) during periods of network congestion. When applied, the service
uses bit patterns in the "DS-byte" of IP, which for IPv4 is Type-of-Service
(ToS) octet.
When you configure DiffServ you apply a priority value to a service and thus
identify it as different to less important services. You do this by arranging
routers or switches that can examine IP headers and prioritize them by the ToS
header octet. The network devices will then apply their rules to prioritize IP
traffic. The AADvance controller maintains the priority when it responds to
incoming messages, and sets a priority according to the configuration for the
messages it sends out.
If you use DiffServ, the controller scan rate can be up to 5 ms larger or smaller
than the scan rate when DiffServ feature is disabled.
The TCP/IP stack can apply the user-specified ToS data in its datagrams
during the TCP negotiation (this is the 3-way handshake, RFC 793). You can
specify this behavior when you set up DiffServ.
NOTE When in Recovery Mode the I/O communications are disabled and the
Application code is not running.
IMPORTANT The DiffServ feature is only available with release 1.3 onwards of the
AADvance Workbench and controller.