3-24 PathBuilder S24x, 26x, and 27x Switch Hardware Installation
Power-Up Diagnostics/Verification
Power-Up Diagnostics/Verification
Introduction Diagnostics run when a node is powered up. Basic tests are run from PROM and
more extensive diagnostics are run during startup.
If the node detects a lack of software, it sends a message to the CTP. The yellow LED
lights and a 2-digit code is displayed. You must initiate a software co ldload if
needed.
Power Up
Sequence This is the power-up sequence.
Node Restarts The three types of restarts are:
• Coldstart
•Warmstart
Default Node
Node Coldstart A node coldstart is similar to a power-up. It follows the power-up sequence except
that it is initiated when the operator presses the RESET button on the front panel or
when certain software faults occur. All calls are cleared along with Event queues. A
Node coldstart loads only configuration memory.
Node Warmstart A node warmstart can be initiated by a software fault or an operator command. It is
identical to a coldstart except for the following:
No diagnostic testing is performed.
Code downloads are not performed unless necessary.
Event logs are not erased.

Function Description

ROM-based diagnostics Local core self-tests. Boots PROM
checksum, MPU test, Program RAM test.
FLASH verification Checksum FLASH image.
Loads RAM diagnostics Uncompresses FLASH diagnostics image
to RAM and executes.
RAM-based diagnostics Tests I/O cards and everything else on card.
Loads RAM operational
software Uncompresses FLASH operation al
software image to RAM and executes.
Verifies Config database Verifies resident CMEM database.