Philips 32PFL3403D/85, Руководство по обслуживанию

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Service Modes, Error Codes, and Fault Finding EN 27 LC8.1U LA 5.
5.6.6 Start-up/Shut-down Flowcharts
On the next pages you will find start-up and shut-down
flowcharts, which might be helpful during fault finding.
POWER STATES
In this chassis, there are six possible power states as follows:
•
Power OFF
• ON
• STANDBY
• SEMI-STANDBY
• Special Panel Mode
• PROTECTION
Figure 5-8 Power States
POWER OFF
In “Power OFF” mode, the system is completely switched “off”
from AC mains. When AC power is applied, the system checks
for last status. Depending on the last standby status stored in
the system EEPROM, this mode can then transit to “ON” or
“STANDBY” mode.
ON
This is the normal operating mode, indicated by the “on” LED.
All the power supply lines are available and depending on the
sub-mode, all the circuits in the system may be active. From
this mode it shall be possible to transit to “STANDBY”, “SEMI-
STANDBY” and “PROTECTION” mode, or to “Power OFF”
mode if AC mains are switched “off”. The sub-modes are:
•
Active Mode (Normal Consumer Mode)
• Service Modes
• Panel Modes
• Factory Modes
STANDBY
The total power consumption of the system in this mode shall
be equal or less than 150 mW. This state is indicated by no
LED when AC mains is switched “on”. Only the standby
controller WT61P7 is operational in this state, where only
+3V3stby power supply is available. From this mode it shall be
possible to transit to the “ACTIVE” or “Power OFF” mode if AC
mains are switched “off”.
SEMI-STANDBY
The semi-standby state is only accessed during transition from
ACTIVE to STANDBY when the auto clock feature is switched
“on”. The clock information download is carried out in this state
before proceeding to STANDBY.
SPECIAL PANEL MODE
The Special Panel Mode is only used during manufacturing
process to program the system EEPROM. In this mode, the
SDA0 and SCL0 ports of MT5382 are set to high impedance
after SDM and PANEL pins are both detected as “low” during
startup. This mode can be exited using a power recycle.
PROTECTION
This state is entered when an error has been detected at
startup or in the “ACTIVE” mode. All switched power supply
lines are turned “off” with only +3V3stby remaining “on”; similar
to “STANDBY” mode. This state is indicated by the blinking red
front LED with the blinking sequence denoting the type of error
detected.
When the system enters the protection mode due to a critical
error, it should be turned “off” and the failure cause needs to be
resolved. The system will function normally again after
performing a power recycling once all protection causing
failures have been resolved.
START-UP SEQUENCE
There are two cases of start-up sequences, namely:
•
AC On and
• Standby Wake-up
See also figure on next page.
AC ON
In the case of start-up from AC mains, all PSU voltages start to
turn “on” as the hardware default of the active “low” STANDBY
(controlled by Standby Controller WT61P7’s STANDBY signal)
signal to the PSU is pulled “low” with respect to ground.
The MT5382 starts running boot loader once the hardware
reset circuit is released. The system will then check the last
standby status from the system EEPROM to determine
whether to complete the system start-up (load image, turn on
the audio, display etc) or proceed to standby and wait for wake-
up command from user. The Standby Controller then proceeds
to verify the power status of the +12V and sends the system to
protection in case of any failures. Special Panel, SDM, and
PANEL modes are detected as well.
System recovery is always handled by Standby Controller.
Watchdog for MT5382 and MT8280 (if present) will be only
enabled during startup, and these components are able to
differentiate the normal startup and watchdog reset to trigger
system reset when applicable. The alive checking mechanism
kicks in after system startup is completed.
STANDBY WAKEUP
When the system receives a command to wake-up from
standby, the Standby Controller sets the STANDBY signal
“low” to turn “on” the switched power, and similarly detects for
the presence of +12V. The MT5382 waits for +3V3_SW to be
available before loading its image. The significance of this
voltage detection is due to the flash is also being powered by
the same mentioned voltage.
The following figure shows the start-up flowchart for both “AC
On” and “Standby Wake-up”:
H_17740_033.eps
230108
Power
OFF
AC Mains OFF
AC Mains ON
ON STANDBY PROTECTION
PSU = ON
LED1 = ON
LED2 = OFF
PSU = STANDBY
LED1 = OFF
LED2 = OFF
PSU = STANDBY
LED1 = OFF
LED2 = BLINK
SEMI-
STANDBY
(Clock
Download)
AC Mains ON
Special
Panel
Mode
SDM && Panel
= LOW
ERROR
detected
ERROR
detected
Last Status = ON
Last Status = STANDBY
Received
WAKEUP Command
ERROR
detected
STANDBY
Command
Manual
Clock
Auto
Clock
AC Mains OFF