KX-NS8290CE - Panasonic PBX Service Manual (repair manual). Page 29

29

START

Check Power Circuit (1.1V/1.8V)
1)Check DC1.1V at TP[+1.1V]-TP[DG].
  If output is NG, check [R115], [R116]
  [R111], [L100], [R117].
2)Check DC1.8V at TP[+1.8V]-TP[DG].
  If output is NG, check [IC103],

[R118], [R125].

TEST_OUT[3:0
= Error

NO

Check BIST Result Code
at TEST_OUT[3:0] pins

[ T E S T _ O U T   B I S T   R e s u l t   C o d e   T a b l e ]

  TEST_OUT     Result Description
  3 2 1 0
  ------------------------------------

  L L L L 0h   BIST Result is OK

  ------------------------------------

  L L L H 1h   Boot ROM Checksum Error

  ------------------------------------

  L L H L 2h   SDRAM Address Line NG
  L L H H 3h   SDRAM Data Line NG
  L H L L 4h   SDRAM R/W Test NG

  ------------------------------------

  L H L H 5h   ARAM Address Line NG
  L H H L 6h   ARAM Data Line NG
  L H H H 7h   ARAM R/W Test NG

  X X X X

YES

END

BIST  (B uilt-In S elf T est) function
 Before hardware initialization, Boot Program executes
 hardware self test. The result is displayed at
 TP (TEST_OUT[3:0]) which is located on component
 side of PCB.

1)Boot ROM Checksum Error
 Boot Program which is stored in NOR
 Flash ROM has several bad data blocks.
 NOR Flash (IC203) should be repaired.

2)SDRAM Concerned Error
 Check DC1.8V and SDRAM[IC200/201]

3)ARAM Concerned Error
 ARAM is CPU(IC100) internal memory.
 If this error is detected, check
 CPU Clock (25MHz) and CPU(IC100)

Check Power Circuit
(1.1V/1.8V)

Check CPU Clock
(25MHz)

Check Reset Signal

Check NOR-Flash
Control Signals

Check CPU Clock(25MHz)
1)Check 25MHz Clock at TP[25MHz].
  If output is NG, check [IC100],
  [X101], [C101], [R102], [R103],
  [R140], [R141].

Check Reset Signal
1)Check TP(RESET) voltage level, if
  this TP(RESET) is low level,
  check [R107], [R108], [R114] then
  goto 2)
2)Check [IC101-1pin], if this pin is
  DC2V, check [R127], [R128], [Q100].
3)If [IC101-1pin] is Low level, but
  TP[RESET] is still Low, [IC101]
  should be repaired.

Error detected
during BIST

NOR Flash Control Signals
If DC1.8/1.1V, Reset, Clock are OK, but
Boot loader doesn't work properly, you
have to check NOR-Flash[IC203] and/or
NOR-Flash Control Signals.
Please refer to [NOR-Flash Waveform]
page, and check if the #CE, #OE signals
work properly.