Configuration Led: C; Signal Led: S; Remote Led: R; Passed Self-Test Led: P - HP 27115A Installation Manual

Configuration LED: C (red, normally off)
When on, the Configuration LED can mean either of two things:
• The jumper J2 is in the wrong position. The HP-FL cannot communicate
with the remote device.
• There is an incompatible response from the remote disk drive.
During troubleshooting,
if a single-fiber loopback cable is installed, the CLEO
will also light with the jumper J2 in the correct position. With a loopback cable
installed, this indication is normal.
Signal LED: S (red, normally off)
When on, the Signal LED indicates that the HP-FL is having difficulty extracting
data from the received signal. Total absence of a signal will cause the LED to
light at full intensity. The PCA updates the state of this LED periodically. The
rate of updating may be thousands of Hertz and the LED may appear to blink or
flicker.
Remote LED: R (red, normally off)
When on, the Remote LED indicates that the remote device fails to respond to
periodic requests for identification. These requests are part of the proprietary
HP-FL protocol.
Passed Self-Test LED: P (green, normally on or blinking)
This LED will light when the PCA has passed its self-test and is operational. It
remains lit unless an error condition on the PCA causes the LED to turn off.
Error conditions that will cause this are link protocol errors, link data parity
errors, and data structure faults. (The system console may report an unexpected
CIO event corresponding to these errors.)
Note that this LED will blink following any form of PCA reset until a "connect
subchannel command" is received from the system processor unit via the CIO
bus. A subchannel establishes a path from the CIO bus to the actual link data
path, and is prerequisite to transferring data between the CIO bus and the
HP-FLPCA.
Activity LED: A (green, normally blinking)
This LED is lit when message frames with proper HP-FL protocol headers are
transmitted onto the link. This is an unpredictable event and depends on HP-FL
requests for link access. Even when no HP-FL PCA requests are pending, the LED
will light whenever the PCA transmits its periodic requests for identification to
the remote device; hence, this LED blinks irregularly and somewhat slowly, 10 to
60 times per minute.
3-4 Troubleshooting and Diagnostics