Chapter 14 : fail-safe system, Overview, Chapter 14: fail-safe system – Horner APG QX751 OCS User Manual
Page 73
MAN0890-02-EN
CH. 14
August 20, 2009
Page 73 of 96
ECN # 979
CHAPTER 14: FAIL-SAFE SYSTEM
14.1 Overview
The Fail-Safe System is a set of features that allow an application to continue running in the event of
certain types of "soft" failures. These "soft" failures include:
• Battery power loss
• Battery-Backed Register RAM or Application Flash corruption due to, for example, an excessive
EMI event.
The Fail-Safe System has the following capabilities:
• Manually backup the current Battery-Backed RAM Register Settings into Flash memory.
• Manually restore Register Settings from the values previously backed up in Flash to Battery-
Backed RAM.
• Detect corrupted Register Settings at power-up and then automatically restore them from Flash.
• Detect corrupted or empty application in Flash memory at power-up and then automatically load
the AUTOLOAD.PGM application file from Removable Media (Compact Flash or MicroSD).
•
If an automatic Register Restore or Application Load occurs, the OCS can automatically be
placed in RUN mode
The fail-safe system can be accessed by going to the system menu of the controller. The menu “Fail-Safe
System” has been added at the end of the main system menu for this. Selecting “Fail-Safe System” menu
will open the following menu screen:
Figure 14.1 – Fail-Safe System