7.1 Self Test
7-2
Memory Test
2. The memory test starts and the results of the test are shown.
Memory Test
Program No : 08501193-01
Boot : BOOTPGN-00
ROM
: OK
SRAM : OK
DRAM : OK
CPU RAM : OK
EEPROM : OK
Battery : OK (3.3V)
Hit any key
The contents of the checking are shown below.
- Memory Test:
Memory Check
on
ROM
built-in U8
Check on checksum
SRAM (Backup)
U10
DRAM U5
CPU RAM
built-in U8
Checked by Read/Write test
EEPROM
U13
Checked by Read/Write test
- Battery:
When the test is performed, the voltage of the backup battery BT1 is checked
and displayed. When a battery is newly installed, the voltage reads about +3.3
VDC. If the Status display field shows
mark, it shows that the battery
voltage has dropped below +2.5 VDC. When this occurs, replace the battery
with a new one. When the battery voltage goes down below +1.8 VDC, it
becomes impossible to back up the storage memory of received messages
(U10: SRAM). In this case, received messages are deleted when the power is
turned off.
Fig. 7.1.1 Backup Battery voltage detection circuit
1
2
J7
BAT VOL
BAT CHECK
Q6
Q9
U11
RES N
SRAM Vcc
Reset IC
CR2450 F2ST2L
BT1
CE1 N
U8
Main CPU
U10
SRAM
Содержание Navtex NX-700-A
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Страница 11: ...Contents 7 Specifications AP1 1 Part List D 1 Contents of Drawings S 0 ...
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Страница 61: ...3 2 NX 700B 3 5 3 2 NX 700B Fig 3 2 1 Front view Fig 3 2 2 Rear view and Side view RECEIVER port GND Terminal ...
Страница 63: ...3 2 NX 700B 3 7 Fig 3 2 5 J2 disconnected Fig 3 2 6 J1 disconnected ...
Страница 67: ...3 4 Antenna unit NX 7H 3 11 Fig 3 4 3 Pre AMP unit Fig 3 4 4 Shield cover of Pre AMP unit removed ...
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