System Problem - Sam4s ER-650 Service Manual

8 Trouble Shooting

8-2 System Problem

System Problem
Reset Signal
Ok?
Y
Power Fail
Signal Ok?
Y
Program
Ok?
Y
SRAM
Ok?
Y
CPU
Ok?
Y
End
8-2
N
1. Check the IC M51953B(U4)
2. Check the 74HC14(U10).
3. Check the RST Pattern on PCB.
N
1. Check the LM393(U12)
2. Check the Power (24V,5V)
3. Check the Pattern on PCB
N
1. Check the Addr/Data line Pattern
2. Check & Change the EP-ROM
N
1. Check the /CS Decoder HC138 (U2)
2. Check the Each SRAM
3. Check the Addr/Data Pattern
N
1. Check the Main Clock(14.7456MHz)
2. Check the Addr/Data Pattern
3. Replace the Main PBA.
SAM4S ER-650 SERIES