Browse Prior Art Database

Visual Representation of Serial Channel Failures

IP.com Disclosure Number: IPCOM000105497D
Original Publication Date: 1993-Aug-01
Included in the Prior Art Database: 2005-Mar-20
Document File: 2 page(s) / 66K

Publishing Venue

IBM

Related People

Bresemann, DH: AUTHOR [+4]

Abstract

The detection of failures in a serial channel interface can be provided with the determination as to whether the failure is due to the control unit or the channel. In a serial I/O connection, the control unit can be a long distance from the channel. The serial channel interface can be operational, not operational due to the channel, or not operational due to the control unit. A visual indication such as a Light Emitting Diode (LED) can be used to indicate the three unique states of the serial channel interface.

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This is the abbreviated version, containing approximately 52% of the total text.

Visual Representation of Serial Channel Failures

      The detection of failures in a serial channel interface can be
provided with the determination as to whether the failure is due to
the control unit or the channel.  In a serial I/O connection, the
control unit can be a long distance from the channel.  The serial
channel interface can be operational, not operational due to the
channel, or not operational due to the control unit.  A visual
indication such as a Light Emitting Diode (LED) can be used to
indicate the three unique states of the serial channel interface.

      In the present embodiment, if the link is operational, the LED
is off.  If the LED is on, the link is not operational due to the
control unit.  If the LED is blinking, the link is not operational
because of the channel or the interconnecting lead, the fiber optic
path.  The microcode senses the operational condition of the link.
The non operational condition due to the control unit, where the
light operates as a solid-on state, can be due to the control unit
internally disabling the link, or being in an initialization state.
Further, the control unit may have been taken off line and therefore
can not be accessed by the channel.  Also the system adapter
interface may be placed in a position where access is not available
or the storage path of the storage cluster can not be accessed and
therefore, access can not be made to the devices connected to either
of the two storage paths.

      The non operational state due to the failure of the channel or
the cable connection, which results in the blinking light, can be due
to the link failure because of the loss of signal or the loss of a
sequence.  The microcode can therefore sense that the sequence is not
operational at all or is set off-line and ther...