System Booting Flow Chart - Yamaha PSR-S550 Service Manual

■ SYSTEM BOOTING FLOW CHART

Power On
E-IC = L (IC7 D12,72Pin)
TxD0 = H (IC7 B7,27Pin)
TxD1 = H (IC7 B6,26Pin)
Set CPU(SWX) port
registers
Initialize
BOOT SDRAM
Initialize Ports
PD2 = H (IC7 V7,263Pin)
PD3 = H (IC7 W7,283Pin)
PD6 = H (IC7 V8,264Pin)
PD7 = H (IC7 W8,284Pin)
PG2 = H (IC7 P2,198Pin)
PG7 = H (IC7 N4,190Pin)
Release PN-IC
PN-IC=L(IC7,W8,284Pin)
/PN-IC=H(IC20,8Pin)
Beginning telecommunication
with panel CPU
IC7, C7, 47Pin=L/H
PN-IC reset
PN-IC=H(IC7, W8, 284Pin)
/PN-IC=L(IC20, 8Pin)
Release peripheral ICs reset
/LCD-IC = H (IC20,4Pin)
Opening screen
will appear
Opening screen will appear.
/LCD-OFF = H (IC20,2Pin)
Release peripheral ICs reset
EICN = H (IC7 D12,72Pin)
Access beginning to the
IC9(Program Flash ROM).
Clock output beginning from
SYSCLK
(IC7(CPU) Y12,308Pin).
Access beginning to the
IC8(SDRAM).
If it does not reach to this
stage, the following IC is
defective.
• PROGRAM FLASH (IC9)
If it is not telecommunicated,
the following points are
defective.
• PNL circuit board
• No connection with CN701
Access beginning to the
IC4(LCD Controller).
Initialize
BACK-UP FLASH
(IC10)
Release peripheral ICs reset.
/DAC-IC = H (IC20,6Pin)
Transmission MKS ACK
Transmissin beginning
TxD1 = L (IC7 B6,26Pin)
TxD1 = H (IC7 B6,26Pin)
It the booting procedure stops here,
there is a possibility that the
following ICs are defective.
• PROGRAM FLASH(IC9)
• SDRAM (IC8)
yes
Test Program
mode?
"Test Mode"
no
Test program
yes
Factory Set
executed?
"All Memory
no
Clearing..."
yes
Backup Clear
started?
"Backup
no
Clearing..."
yes
Song Clear
started?
no
Clearing..."
Main screen
will appear
Main program
routine
* "Factory Set" refers to the condition of turning on the power after
executing "Factory Set" in the Test Program.
PSR-S550/PSR-S550B
Access beginning to the
IC10(Backup Flash ROM).
by RxD1,SCK1.
routine
BACK-UP FLASH(IC10) is
defective when the
"All Memory Cleaning..."
is displayed every time.
BACK-UP FLASH(IC10) is
defective when the
"All Memory Cleaning..."
is displayed every time.
BACK-UP FLASH(IC10) is
defective when the
"All Memory Cleaning..."
is displayed every time.
"Flash
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