Lexicon MPX 110, Service Manual

Page: 26 / 75

MPX 110 Service Manual
5-8
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 INTERRUPT TIMER TEST (4)
This is the same test that resides in the power on diagnostics. It was included in the Extended Diagnostics
for troubleshooting purposes.
The Interrupt test will verify that the interrupt (ZINT/) is working and occurring at the proper intervals. The
Lexichip3 will provide MPX 110 with the interrupt (ZINT/) to the Z80's maskable interrupt line. The interrupt
test will run for a period of time that allows 20 interrupts to occur. A count of the interrupts is kept and
compared for overshoot and undershoot. Greater than 21 interrupts means the interrupt is too short and
less than 19 interrupts means it's too long.
When selected, the Binary LED’s will read the following:
Edit Bypass Store Tap
O O O
l
MSB LSB
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 AUDIO DATA FILE TEST (5)
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 verify that the Lexichip3 Audio Data File memory is working.
The Audio Data File (ADF) is a fast synchronous 128-word SRAM that provides audio data buffering and
storage for: external memory references, Serial I/O, and the Host-to-Lexichip data port. ADF locations also
function as ARU Registers and as scratchpad memory. This test will verify that the Lexichip3 Audio Data