Emerson PACSystems RX3i User Manual page 98

PACSystems™ RX3i and RSTi-EP CPU Reference Manual
GFK-2222AK
4.5.1.3 STOP-Halt Mode
The CPU will automatically go into STOP-Halt mode and suspend logic execution and I/O
scanning for the following conditions:
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To recover from STOP-Halt mode, the CPU/CPE must be disconnected from its backup
power source (battery or Energy Pack), powered off, then powered back on, after which
the backup power source should be reconnected. The CPE400/CPL410 provides an
alternative way to recover from STOP-Halt mode by means of the OLED display and
without the need of removing the Energy Pack. The section below described this
alternative.
To enable backplane communications where they have been disabled in STOP-Halt mode,
cycle power with its backup power source attached (battery or Energy Pack).
While the CPU is in STOP-Halt mode, the PACS Analyzer tool may be employed to
examine the CPU's fault tables. The PACS Analyzer software is a tool that is embedded in
PME. It can also be downloaded from Emerson's support website. (See link located at the
end of this document.)
If backplane communications have been suspended, the PACS Analyzer must be directly
connected to a serial or Ethernet port on the CPU. If backplane communications are
operational, the PACS Analyzer may be connected via a communications or Ethernet
module in the backplane, or to a CPU-embedded port.
RX3i CPE302/CPE305/CPE310/CPE330/CPE400/CPL410 and RSTi-EP CPE100/CPE115 CPU
models only: The programmer can connect to these CPUs in STOP-Halt mode through the
embedded Ethernet port without a reset or power cycle.
4.5.1.3.1 Recovering from STOP-Halt mode (CPE400/CPL410 Only)
The CPE400/CPL410 provides the ability to recover from STOP-Halt mode using the OLED
display and without the need of removing the Energy Pack. This recovery mechanism is
particularly effective when the PLC is configured to power up in RUN mode from Flash and
the user logic contains code that causes the CPU to go into STOP-Halt mode (e.g.,
exceeding Software Watchdog, or accessing an illegal memory location from a C-Block).
Once the user applies the STOP-Halt recovery mechanism the CPU will automatically
reset and will come up in STOP mode, preventing executing of the offending user code.
At this point the user can connect to the CPU and perform the necessary changes.
The following are the steps to apply the STOP-Halt recovery:
1. Collect a PACSAnalyzer trace prior to performing the rest of the steps. Once the
CPU Operation
Software Watchdog timeout
ECC Memory Check fault
Illegal memory access from a C-Block
Hardware Watchdog timeout. This condition resets the CPU and suspends
backplane communications.
recovery is applied, the CPU clears its Energy Pack memory. The User Flash
memory is not automatically cleared.
Section 4
October 2019
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