4. system clock select and cpu setting – Curtis AR-B1682 User Manual
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2-4. SYSTEM CLOCK SELECT AND CPU SETTING
System clock and CPU frequency ratio are automatically detected by BIOS. Please keep sw2 ,
sw3-1 , sw3-2 ,and sw3-3 off.
2-5. RS232/485 SELECTION
The jumper settings are as follows:
(1)COM 1 & COM2 (RS232)
1
2
3
J1
Terminator
1 2 3
J2
7 8 9
1 3 5
J3
2 4 6
(2)COM 2(RS485)
1
2
3
J1
485+
485-
Terminator
1 2 3
J2
7 8 9
1 3 5
J3
2 4 6
2-6. DOC MEMORY
(1) DOC Memory Mapping Selection (JP6, JP7)
A 32-pin DOC socket supports a DOC (Disk-on-Chip) up to 72Mb. This PnP Flash ROM DOC can
be installed as one of the user’s hard disk drive. And if set as Drive C, it can be used to boot up
the computer with MS-DOS installed. It offers much faster access than a floppy or hard disk and
greatly increases reliability under harsh environment.
The DOC Memory Mapping is as follows:
DOC Memory Map
JUMPER SETTING
(pin closed)
JP6 JP7
JUMPER
ILLUSTRATION
Manufactory default --- CC000h-CDFFFh
(2) DOC 2000 SEG (SW1)
On
2 4 6 8
1 3 5 7
SEG
3-4
5-6
7-8
CC00H
ON
ON
OFF
D000H
ON
OFF
ON
D400H
ON
OFF
OFF
D800H
OFF
ON
ON