Kurzweil CUP2, Service Manual

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Description of Tests
SDRAM Refresh
This test veri  es the write/read functionality and accuracy of the SDRAM chip (U2) attached
to the microprocessor, SH7203 (U1).
A failure of this test indicates a problem with the SDRAM chip or associated circuitry on the
Engine Board.
MIDI UART
This 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 the MIDI Out jack to
MIDI In jack on the CUP2‘‘s rear panel).
If a MIDI cable is not connected between CUP2‘‘s two MIDI jacks,
ER
will be in the display. If
you press the Play/Stop button, the display scrolls ““
Connect MIDI OUT to MIDI IN
.””
A failure of this test could be caused by failure of the serial port, other MIDI circuitry, or a
problem on the Engine Board.
Internal Flash
This test veri  es the manufacturer ID and the size of the NAND Flash installed. The test then
writes and reads back one or more blocks not occupied by the  le system. This test also
indicates if the NAND Flash is formatted or unformatted.
A failure of this test may indicate a problem with the microprocessor (U1), NAND Flash (U3),
CPLD (U11), or related circuitry on the Engine Board.
MARA Validity
Note:
Throughout this manual many references are made to the MARA IC. For service
personnel unfamiliar with the CUP2, MARA is the name given to the Kurzweil Custom Sound
IC.
This test veri  es the proper content of certain read-only registers and the read/write accuracy
of certain read/write registers on MARA. It also writes and reads back the various register
blocks in MARA that are implemented as RAM cells.
A failure of this test may indicate a problem with the microprocessor (U1), MARA (U5), or
related circuitry on the Engine Board.
Diagnostics
Description of Tests
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