Korg DSS-1 - 10. Main Circuit Explanation; KLM-780 CPU Board

ITEST MODE EXPLANATION
1. Turn power ON (of course while simultaneously
pressing section A data entry switches es e^) and
select the DSS-1 internal inspection mode.
Note:
If this indication appears, you can assume that CPU
1 and the LCD are operating normally.
2. One to two seconds later an indication that the test
mode has been entered appears. The internal ROM
version No. and the creation data are indicated
simultaneously.
Note:
If there are problems on the TG circuit board, the
system does not proceed to the TEST MODE indica
tion.
3. Use the cursor (Y/N) to select whether or not the
floppy disk drive is to be inspected. If NO, proceed
to step 12.
4. Cursor (Y/N) key judgment
5. Insert a previously formatted medium and ask the
system whether it is all right to write in (save) test
data for that medium. This is also selected by the
cursor (Y/N).
6. Cursor (Y/N) key judgement
7. Save test data for the medium (while writing in).
9. Errors: "refer to S-1"
10. From the results of reading and writing the test data
for the medium, an indication that the FDD is normal
is given. Asks whether it is necessary to try one
more time.
11. Cursor (Y/N) key judgment
12. Asks whether to perform a TG (KLM-782) WAVE
RAM check.
13. Cursor (Y/N) key judgment
14. The data 0000 0000 0000B are written in to the
12-bit WAVE RAM on the TG circuit board 1 bit at a
time; if the writing can be done until the last ad
dress, the fact that they are 0000 0000 0000B is
read in.
18. The data 1111 1111 1111B are written in to the
12-bit WAVE RAM on the TG circuit board 1 bit at a
time; if the writing is completed to the last address,
then the fact that they are 1111 1111 1111Bisread
in.
21. Each write/read operation is performed, and the fact
that the WAVE RAM is normal is indicated.
22. Check whether or not the "DEL/CANCEL" works.
If it doesn't work when pressed (system does
not proceed to the next step) then the switch is bad,
24. Similarly, check whether the "COMPARE" switch
works.
26. The checks in the internal inspection mode shall be
passed.
27. W^RAM error; refer to "S-2".
4
1
'S-1" FDD ERROR MESSAGES
Note:
(D-DDH-D) = (D-DDH-^)!
- Physical sector number (1 to 5)
-Cylinder address (00 to 4F)
-Head number (0 or 1)
37
Scan by Manual Manor
http://www.markglinsky.com/ManualManor.html