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I/O Ports Checkout
Note: Be sure to enable the serial and parallel ports in
the BIOS setup utility before performing diagnostics
tests on the I/O ports.
Also, be sure to write down the I/O address for the
serial port to identify the port in the diagnostic test.
Do perform a diagnostics checkout on the I/O ports:
1. Boot from the diagnostics diskette and start the
program.
2. Go to Diagnostics on the main menu and select
Serial Ports or Parallel Ports.
Note: If you want to do a check on the infrared port,
select Serial Ports.
3. In the Serial Port Test Category, you can check four
items:
Registers and Interrupts
Internal Loopback
External Loopback
FIFO Buffers (16550A)
Move the cursor to the item you want to check, and
press Enter. Then follow the instructions on the
screen.
Note: To do an External Loopback test, you must
have a Loopback plug.
4. In the Parallel Port Test Category, you can check two
items:
Command And Data Port
External Loopback And IRQ
Move the cursor to the item you want to check, and
press Enter. Then follow the instructions on the
screen.
Note: To do an External Loopback And IRQ test,
you must have a Loopback plug.
Power Management Features
Three power management modes are available in the com-
puter system to reduce power consumption and to prolong
battery life.
Standby Mode:
In standby mode, the following
occurs:
The LCD backlight turns off.
The hard disk drive motor stops.
Events that cause the computer to enter standby mode:
Standby mode requested by the Fn key (Fn+F3).
ThinkPad 240
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