960L Functional Diagnostic Descriptions - Lexicon 960L Service Manual

correct operation. The reverb card has 8 LEDs along the front left edge on the side of the card that faces
the NLX motherboard, when the card is observed mounted in the 960L chassis. When powering on the
960L and executing the 960L application, (allow it to boot to normal operating mode), the LEDs will initially
be off for about 1 minute 45 seconds. Then all the LEDs will be lit very quickly. After that the 4 leftmost
LEDs, D1-D4, that are labeled Z80 #2, Z80 #2, Z80 #1, and Z80#1 respectively, will light in a periodic
pattern where D1 and D4 the two outside LEDs will be on and the other two off and then D2 and D3 the two
inside LEDs will be lit and the two outside LEDs will be off. This pattern will occur 4 times and take about 7
seconds. Then all four leftmost LEDs D1-D4 will be all lit for about 5 seconds. Finally the five leftmost LEDs
D1-D5, where D5 is labeled SYSTEM OK will be lit, and the process is completed. The total time to perform
the entire operation takes approximately 2 minutes.
The NLX motherboard has beeping that assists the technician. The first beeping occurs at 13 seconds and
is 2 quick beeps to indicate no keyboard is present. The you will hear floppy drive and CD-ROM motor
activity. The second beep occurs at 21 seconds and is 1 beep to indicate the BIOS is completed loading
and the operating system is beginning execution. If no beeps or any other beeping pattern occurs the
motherboard is not booting properly and a system level failure has occurred.
In the event of a failure the first thing to check is the power supplies. After that the motherboard is suspect
and should be swapped out with a known good motherboard. Extreme care should be exercised when
changing a motherboard. The bottom of the motherboard must never be allowed to come into contact with
the metal chassis of the 960L. The motherboard contains a lithium battery with a thru-hole battery holder. If
the leads of the battery holder come into contact with the metal chassis the battery will be shorted out and
permanent damage can occur. Also the amount of force required to insert the NLX motherboard into the
NLX connector is considerable. The contact pins are small and it is very easy to misalign the pins in the
connector or not fully seat the motherboard giving rise to false failures. To ensure fully seating the
motherboard verify that the right notched edge of the motherboard is almost against the NLX connector on
the NLX backplane and that the threaded standoffs in the front of the chassis are up against the slot cutout
of the motherboard support bracket.
If the 960L still won't boot and the power supplies are good and a known good motherboard is installed
correctly, the next thing to verify is the reverb card. After that verify the CD-ROM, hard disk drive, and
floppy drive are working.

960L Functional Diagnostic Descriptions:

NOTE – The nomenclature for the four Lexichip3s on the reverb card will be Lexichip3 followed by a space
and then the number of the Lexchip3.
The 960L functional diagnostics verify that the 960L can pass MIDI data from the Out to In ports, the two
serial ports function, most of the reverb card functions, and the cards in the I/O cage can read and write to
registers on their respective FPGA's or CPLD. The following sections describe the diagnostic tests
available. The syntax for the diagnostics is listed in the first line. For troubleshooting purposes a PS/2
keyboard can be connected to the LARC2 prior to powering on the 960L and individual diagnostic tests can
be executed any number of times by typing the diagnostic test name followed with the optional number of
times desired. A 0 entered means to run the test forever until a key is pressed on the keyboard. If no
number is entered the test runs once and stops. This is the default version. The default version of all the
following tests are executed by running the complete system script, which is number 1.
In order to access executing individual tests the correct path to where sets of test are located must be
entered on the keyboard. The following directories/folders exist:
MIDI Tests:
Reverb Card Tests:
Serial Port Tests:
I/O Card Cage Tests:
The MIDI tests reside in a directory called MIDI.
The reverb card tests reside in a directory called reverbcardtests.
The serial port tests reside in a directory called serial.
The I/O card tests are in directory called IOBackPlane
Lexicon
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