Cd Load Error Detection - Kenwood KDC-MP732 Service Manual

4. Display specification
• Display the "PROTECT" string and blink all characters at
1Hz.
∗ Use the indication below with the highest priority (error mes-
sage), and maintain the error message even when the
source is changed.
Display Example
( Blink alternately
at 1Hz
PROTECT
Cancel Condition
• Press the Reset terminal on the main body. or set Backup
to OFF (Unplug and plug back in the DC connector).
The history is maintained (E2PROM data is saved).
Overview
Record the number of times when mechanism error (SW er-
ror) occurred at CD LOAD.
LOAD error recording shall be done in 2 patterns, by the SW
status illustrated below.
LOAD error is established when LOAD operation is not com-
pleted after LOAD operation is started before the protect timer
count is completed.
Clearing of record is done in the following situations:
1) After reset is cancelled, when reading EEPROM, the code
is NG.
2) While in test mode, the specified key (Play/Pause key
pressed for 2 seconds) input.
3) When in EEPROM all-clear initialization mode (refer to
the test mode specification document)
• Display is shown on the test mode specification document.
• Number of times with error(s) is 99 at MAX.
• Not recorded in test mode [1+3 keys].
DC OFFSET ERROR

CD LOAD ERROR DETECTION

KDC-MP732
Note while in test mode
• While in test mode, even if DC leak is detected, it is not
written into E2PROM.
When an error is detected, the display is enabled.
Other
• Function for checking and clearing data in E2PROM by a
given key shall be included.
(Used at production dpt. and service center, etc.)
Operation
LOAD
SW1
(LOS SW)
SW3
(12EJE SW)
SW4
(LOE/LIM SW)
ERR condition
LOAD_ERR1
∗ Trigger for starting the sequence: detecting the inserted disc
with SW 1 and 3 LOW edge.
(As an exception, protect LOAD when EJECT error)
q If the protect timer was counted up before the LOS (SW1)
up edge detection, it is recorded as LOAD_ERR1.
w If the protect timer was counted up after the LOS (SW1) up
edge detection, before the LOE/LIM (SW4) up edge detec-
tion, it is recorded as LOAD_ERR2
∗ When DISC was inserted briefly but pulled out immediately
(DISC is detected but not inserted), it is considered as an
error.
Special case: Even if LOS (SW1) up edge is not detected, if
LOE/LIM (SW4) up edge is detected, it is still recorded as
LOAD_ERR1. Also, if SW4 up edge is detected, the motor is
stopped.
q
w
Effect
LOAD_ERR2
21