Sram Test (2); Lexichip3 Wcs Test (3) - Lexicon MPX 110 Service Manual

SRAM TEST (2)

The SRAM Test performed during the Extended Diagnostics is a non-destructive test. The non-destructive
test will test one memory location at a time, saving the contents from the location being tested into a
register, and then restoring the value when it's done. The entire contents of the SRAM is tested by writing
00 hex (00000000 binary), and verified by reading the same value back from each memory location. This
write/read sequence is also performed using the following patterns: 55 hex (01010101 binary), AA hex
(10101010 binary) & FF hex (11111111 binary).
This test was included in the Extended Diagnostics for troubleshooting purposes.
When selected, the Binary LED's will read the following:
Edit Bypass
O O
MSB
Pressing the STORE button will execute the test.
Pressing the TAP button will run the test continuously
The remaining buttons, encoders, ADC Pots and footswitches (2) are inactive. When the test is executed,
all Front Panel LED's will go off.
If the test passed, the L & R Level (green) LED's will light.
If the test failed, the L & R Clip (red) LED's will light.
To run the test again, press the STORE button.
To run the test continuously, press the TAP button.
To stop the test from running continuously, press the STORE button.

LEXICHIP3 WCS TEST (3)

This is the same test that resides in the power on diagnostics. It was included in the Extended Diagnostics
for troubleshooting purposes.
This test will check the RAM program memory space ( writeable control store) of the Lexichip3. The WCS
(memory space) is first filled with the value 55 hex (01010101 binary), then each memory location is read to
see if it contains 55. If 55 is in the memory location, the location is filled with AA hex (10101010 binary), and
the next location is processed. Once the RAM has been checked for 55's and filled with AA's, the process is
then repeated checking for AA's and storing 0's into memory. Following this test is an Address test to verify
all the address lines are active. Finally, the memory is checked for 0's.
When selected, the Binary LED's will read the following:
Edit Bypass
O O
MSB
Pressing the STORE button will execute the test.
Pressing the TAP button will run the test continuously
Store Tap
l
O
LSB
Store Tap
l
O
LSB
Lexicon
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