AT&T 6300 Service Manual page 244

DIAGNOSTICS
MENUD
The purpose of MENU D is to allow you the option of testing all of
the installed hardware or specific modules. If you choose to test
the hardware multiple times, MENU D prompts you to indicate the
number of times (loops) the hardware is to be tested. This is
helpful if the customer is experiencing intermittent faults.
After you indicate if the tests are to be performed once or multiple
times, MENU D is displayed:
1 - MAIN BOARD
3 - XXX KB MEMORY CXXX = total system RAM)
4 - 83 KEY KEYBOARD
5 - XXXX VIDEO SYSTEM (XXXX = COLOR or MONOCHROME)
6 - 1 PARALLEL PDRT(S)
7 - 1 SERIAL PORTCS) (USING 8250)
8 - X 48TPI FLOPPY DISK DRIVECS) CX=1 or 2)
9 - X MB HDU DRIVE AND CONTROLLER (X-10 or 20 ME)
To test all listed hardware, press the ENTER key only.
To test individual hardware functions, enter the desired test
number(s), with spaces between the numbers, and then press
the ENTER key.
The hardware to be tested is selected by entering the
corresponding numbers, separated by spaces. To select all the
hardware, press just the ENTER key.
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