General Information; Diagnosis; Power On Sequence - Pioneer VSW-1 Service Manual

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7. GENERAL INFORMATION

7.1 DIAGNOSIS

7.1.1 POWER ON SEQUENCE

Power ON
Power ON
CPU I/O port setting
Wait for one second by software timer
RAM initialization
SW status reading
Event timer interrupt setting (for 2m seconds)
VSYNC interrupt setting
To main processing
Main Processing
Perform the monitoring of the SW status and fader status and judge the chattering by event timer interrupt handling of
every 2m sec.. And perform the processing of each timer value.
Perform the switching and setting of the video signal by a timing of interrupt of VSYNC signal.
2m sec. event timer interrupt handling
2m sec. event timer interrupt
10m sec. timer process
(Count 5 times for 2m sec.)
1 sec. timer process
(Count 100 times for 10m sec.)
VSYNC interrupt processing
Perform switching and setting
of a requiring video in accor-
dance with VSYNC
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• Timer count of 10m sec.
• Switch status monitor and chattering judgment
(SW A, SW B, AUTO, PAL/NTSC and chroma sync selection)
• Fader status monitor and chattering judgment
(A start/stop, B start/stop)
• Chroma control start timer-count and execute of chroma control processing
• V sync limit timer, 30m sec. timeout monitor and execute processing in time-out
• Timer count of 1 sec.
• PLL stability timeout monitoring for chroma control processing
• PLL reset completion processing
• PLL reset timer-count for chroma sync
• Switching of video A/B
• Switching of video system PAL/NTSC (PLL reset at switching)
• Delay value setting of chroma sync processing
• Setting of chroma sync processing start time (execute after 8m sec. from VSYNC processing)
VSW-1
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A
B
C
D
E
F
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