HP OmniBook 800CT Service Manual page 38

received is echoed back to the host. The IR port is first tested in slow mode by sending /
receiving data packets at 115K baud. If this passes, then data packets are transmitted in high
speed at 1 megabit then 4 megabit. These IR transmission tests are repeated 3 times.
Serial port
Levels: 1,2. The level 1 test checks the internal operation of the serial port and does not require
a loopback. The internal registers are pattern tested to ensure the port can interrupt the system.
Then an internal loopback tests for proper internal character transmission. Finally, operation of
RTS, DTR, CTS, and DSR status signals are checked.
The level 2 test performs what level 1 does plus a test at various baud rates for successful
transmission of characters through a loop back connector.
Printer port
Level: 2. This test checks for command and data ports with the 18 data patterns, then uses the
parallel loopback connector for proper operation of signal lines and IRQ generation.
Hard disk
Levels: 1,2,3. The level 1 test checks to ensure the internal drive signals are functioning
correctly; if no errors occur the capacity of the drive is reported. The level 2 test checks all
sectors on the outermost and innermost tracks as follows: a sector of data is read, the data is
inverted and written, the data is read again and verified for correctness, finally the original data is
written back. At level 3, all data between the inner and outer tracks are read to ensure data
integrity. Any failure aborts further testing.
Note that the internal hard disk remaps the physical characteristics of the drive to a logical
collection of tracks, heads and sectors.
Floppy disk
Levels: 1,2,3. This test operates similarly to the hard disk test. Note that the level 1 test does
not require that the floppy disk be connected.
Battery
Level: 2. This test simply reports the status of the charging system: battery type (none or lithium
ion); charge state (NA - battery powered (no AC), NC - no charging, the battery is full, FC - fast
charging, TC - trickle charging, or EC - error charging); percent of battery charged (0 - 100);
battery voltage, and ambient system temperature (Celsius).
SCSI loopback
Levels: 1,2,3. The level 1 test requires a dock or SCSI cable, the devices are checked for
properly terminated signals. At level 2, an attached loopback device checks for opens and
shorts. At level 3, the level 2 test is run, then the user is prompted to remove the loopback, then
the level 1 test is run.
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