Instruction manual

Hardware Overview
025-9416 19
JP9JP10
JP6
a
b
JP12
JP3
JP1
JP2
JP8
JP14
JP7
JP4
JP13
JP5
JP11
a b
a
b
a
b
a
b
Front of
Model 640
Chassis
Figure 4. Main Board Jumper Locations (Top View)
The jumpers are used as noted in Table 2.
CAUTION
Jumpers 1-9 and 11 on the main processor motherboard (Part No. 702-9673) should not
be changed. These jumpers are factory set, based on the custom system ordered. This
information is provided for reference only.
Table 2. Table 2. Main Board Jumper Settings
Jumper Function Settings Default
JP1 Sets ROM memory size
IN
OUT
IN
JP2 Identifies ROM memory size
IN
OUT
IN
JP3 Provides reset to the keyboard interface port
IN - reset
OUT
OUT
JP4 ISA interrupts expansion
IN
OUT
OUT
JP5 Disables watchdog timeout during initialization
A
B - disabled
A
JP6 RESERVED
A
B
B
JP7 Disables RAM parity error interrupt
IN - disabled
OUT
OUT
JP8 Sets non-volatile RAM size
A
B
A
JP9 Enables RAM disk reformat (in conjunction with JP10)
IN - reformat
OUT
OUT