Kurzweil Mark Pro 2i, Service Manual

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Mark Pro TWOi
29
Delay RAM
This test performs a quick read-write of the internal RAM and verifies that the data was
successfully written and retained. A failure of this test may indicate a problem with the RAM or
the Engine Board.
Sine Wave
This test generate sine wave from MARA, wave sample located in Sound ROM, and plays
through DAC and analog audio output. A failure of this may indicate a problem with a MARA
or Sound ROM (U47), or the analog audio section including DAC and OP-AMPs.
Caution
:
The output level of sinewave test is very loud!
.
MIDI
The MIDI test performs a loop-back of the serial port by sending a 23-byte pattern over the
external MIDI link. This test requires a MIDI loop (a MIDI cable that connects two MIDI jacks).
The test will fail if a MIDI cable is not connected between two MIDI jacks. Be sure to run this
test with MIDI cables connected as follows:
Note : Be sure to use a known working MIDI cable!
1. Connect a MIDI cable to the MIDI In and MIDI out jacks and run the test.
A failure of this test could be caused by failure of the serial port, other MIDI circuitry, or a
problem on the Amp Board or the Engine Board.