Sony SDP-EP70, Service Manual

Page: 14 / 75

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3-2. Display of History of DSP Operations
• When “DSP error detected!” is displayed on the fluorescent dis-
play tube, the history of DSP errors will be displayed eight seconds
later. (See Fig. 1.)
• This history will be displayed if a DSP error has occurred in the
past. It helps the detection of malfunction parts by enabling past
problems of the unit to be checked.
• This history shows the “Cause of error” and “How many times
occurred” for the two DSPs. (See Fig. 1.)
Fig. 1
Corresponding DSP
Contents of fluores-
cent display tube
: 1st DSP (DSP56009) 2nd DSP (SSP424023)
: 1 2 3 x 0 0 0 0 1 2 3 x 0 0 0 0
↑ ↑
4
↑
3
↑
2
↑
1
↑
4
↑
3
↑
2
↑
1
:
How to read the
display
4. Operation Check Mode
• During the operation check mode, functions can be set by press-
ing the corresponding button. (See Table-3.)
• Each time a button is pressed, the corresponding function will be
displayed for about 8 seconds.
• Buttons other than those displayed in Table-3 operate usually.
NOTE: Do not press the SET UP button during the operation
check mode. As this button is provided with a special
function for debugging, pressing it may impede the normal
output of signals in the sub-woofer mode.
Table-3:
Button
Function
Outputs the Lch DIGITAL-2 input signal
to the REAR Lch and the Rch to the REAR
Rch.
Fluorescent
Display Tube
Display
Outputs the Lch DIGITAL-3 input signal
to the CENTER and the Rch only to the
WOOFER.
Outputs the Lch DIGITAL-4 input signal
to the FRONT Lch, REAR Lch, CENTER,
and the Rch to the FRONT Rch, REAR
Rch, and CENTER.
DIGITAL2
DIGITAL3
DIGITAL4
OFF
DIG-2
(L-SL, R-SR)
DIG-3
(L-C, R-SW)
DIG-4
(L, R-ALL)
Whole fluorescent display tube lit check
Each time the button is pressed, the fluorescent display tube
lights up as follows.
Lit totally
n Lit partially 1 n Lit partially 2 n Lit totally....
By pressing the MENU knob and displaying “<<< LEVEL ADJUST >>>”,
and rotating the +/– knob to the right, the input signal selected at that time
can be output to any Lch or Rch channel.
(See Table-4.)
Table-4:
Fluorescent Display
Tube Display
Output Destination of Input Signal
Outputs the FRONT Lch/Rch signal only to
the REAR Lch/Rch.
Outputs the FRONT Lch signal only to the
REAR Lch, and FRONT Rch signal to the
REAR Rch.
Outputs the FRONT Lch/Rch signal to the
FRONT Lch/Rch, the REAR Lch/Rch signal
to the REAR Lch/Rch, the CENTER signal to
CENTER, and the WOOFER signal to
WOOFER as usual.
Outputs the FRONT Lch signal to the FRONT
Lch, REAR Lch, and CENTER, and the
FRONT Rch signal to the FRONT Rch, the
REAR Rch, WOOFER.
Exchange (L-SL, R=SR)
Exchange (L-C, R=SW)
Exchange (NORMAL)
Exchange (L, R-ALL)
Number of times the error has occurred
↑
How to read the display
• The left side shows the errors of the first DSP (DSP56009:MAIN
board IC424) and the right side shows the errors of the second
DSP (SSP424023:MAIN board IC423).
• The “How many times occurred” indicates the number of times
that the error has occurred. If an error has occurred more than
256 times, it will be displayed as 256.
• The
1 2 3 4
part shows 0 or 1 according to the cause of the
error. If an error has occurred, 1 will be displayed. If no error has
occurred, 0 will be displayed. (See Table-2.)
Table-2:
Cause of error Possible cause
Mostly due to faulty connection (soldering) be-
tween DSP and microprocessor
Faulty DSP clock (X401 and onwards), faulty
DSP part, etc.
Overrunning of DSP due to heat, microproces-
sor bugging, or IC301 (MAIN board PLL) is
faulty
Faulty DSP part, or faulty microprocessor part,
etc.
1
Failed in initial
booting
2
DSP does not
operate
3
Communication
port malfunction
4
No reply from DSP
NOTE: This history is memorized in the EEPROM until the unit
is initialized. (Refer to “5. Initialization” on page 15.)