User's Manual

omdiag: Using the Diagnostic Service 33
omdiag chassis serialport
Use the omdiag chassis serialport command to test all 9-pin (AT) and 25-pin (PC, XT, and PS/2) serial
ports. The following tests are performed:
• Serial Port Register Test — Writes different data-patterns to the read-write registers of the serial port,
reads them back, and verifies the data against the written data. If this test detects differences between
the written and read data, it logs an error message and the test fails.
• Internal Loopback Test — Tests serial ports that have an internal loop-back mode, specifically for
testing. This test uses the internal loop-back mode to transmit and receive data and compare that the
data received is the same as the data transmitted. The write-only and read-only buffers are tested. Error
conditions such as buffer overrun are also detected.
• Baud Rate Test — Verifies the speed of the port against the system clock to ensure that the baud rate is
within an acceptable range. The baud rate is controlled by writing appropriate values to the Divisor
Latch bytes. The port transmits and receives (in internal loop-back mode) for 2 seconds, and checks
whether the number of characters transmitted and received is two times the baud rate divided by 10
(10 bits are used to transfer 1 byte).
• Interrupt Test — Verifies that the serial port is generating or receiving interrupt requests (IRQs) correctly
when key events occur. Otherwise error events are generated and the test fails.
NOTICE: This test may disrupt normal operation of a device connected to the serial port, for example, a modem. It
is recommended that any connected external device is turned off when this test is running.
omdiag chassis usbctrl
Use the omdiag chassis usbctrl command to test the USB controller(s).
The USB test performs the following test:
NOTE: The following test is available on systems running supported Microsoft Windows and Red Hat Enterprise
Linux (version 3) and later operating systems.
NOTE: On systems running supported Red Hat Enterprise Linux operating systems, connecting or removing a
USB device from the server while the diagnostics enumeration is in progress, may cause the system to hang.
• USB Node Detection Test — Scans the USB bus, enumerating all the USB devices connected to the
USB controller being tested. USB diagnostics enumerate the various kinds of USB controllers on the
system board. In addition to the on-board USB controllers, the package enumerates USB controller
cards inserted in the PCI slot and any other USB devices connected to the ports of these
USB controllers. This test examines hot plugged and unplugged devices from the tested USB controller.