Yamaha n8 Service Manual page 69

(11) Test results will appear. (Photo 8)
• Example of executing screen
(Photo 8)
2. Service test
2-1. Memory check (01 CPU/MEMORY)
2-1-1. Outline
Executes read/write tests of the fl ash ROM and RAM connected
to the CPU.
2-1-2. Test contents
• Test contents of fl ash ROM around the SSP1
Conducts signature ID read test for flash ROM connected
to the SSP1 (Main). Issues command sequence for reading
signature ID of fl ash ROM. Checks if the ID is properly got
to check if it is possible to read and write.
• Test contents of SRAM around the SSP1
Writes data derived from data bus data to specifi ed address by
changing it in increments of one bit and check if the data can
be read properly. Writes specifi ed data to all the power-of-two
addresses and reads the data from all the addresses to which
the data are written, and compares the written data with the
read data for checking.
• Test contents of SDRAM around the SSP1
Conducts read/write tests for the SDRAM of SSP1 (Sub)
through the register for SDRAM access from the SSP1 (Main).
Writes specified data to all the power-of-two addresses and
reads the data from all the addresses to which the data are
written, and compares the written data with the read data for
checking.
2-1-3. Execution of test from PC
(1) Transmits the MIDI command (A0 41 00) to execute the
test.
(2) MIDI command (A0 41 02) will be received if the test
result is OK and MIDI command (A0 41 03) will be
received if the test result is NG.
• Example of executing screen
* Refer to "3. List of test items" for details. (Page 80)
2-2. Switch input test (02 SWITCH)
2-2-1. Outline
Tests if the switches are turned ON/OFF correctly. The switch
input test also serves as test for interruption line from the
E-BUS. If the result of the switch input test is OK, it means
that the test result of interruption line from the E-BUS is OK
as well. Check all the switches including the foot switch.
2-2-2. Test contents
When the test is started, all the LEDs which are attached to
switches will light.
The ON/OFF test will start from the switch on the upper
left portion of the panel. As for lock-type switches, turn ON
and OFF each switch for checking. (Refer to page 71, 72 for
operation procedures)
If the result of the ON/OFF test is OK, the LED of the switch
will go off.
The switches without LED are tested in combination with
an adjacent switch with LED. For example, the LED beside
the [A.IN/DAW] switch will go off when all the results of
switch tests for the [PAD], [
switches are OK. When the ON/OFF tests for switches on the
panel are fi nished, connect the foot switch to the [FOOT SW]
jack. (Refer to "Wiring diagram for service test" on page 65.)
Depress the foot switch and then release it.
If a switch other than the switch to be tested is pressed or
plural switches are turned on simultaneously, the result will be
NG and it is impossible to proceed to the next switch test.
If ON/OFF test for all the switches to be tested is fi nished, the
switch test is completed.
If the result of ON/OFF test of a switch is NG and it is
impossible to proceed to next test, press the [
and [REC] key simultaneously to abort the test.
n8/n12
], [PHASE] and [A.IN/DAW]
A
] (STOP) key
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