Shuttle HOT-681, User Manual

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Multiplier JP6
(66)
MHz
6.5X 433
7X 466
7.5X 500
8X
Jumpers
HOT-681 mainboard features a clock generator to provide adjustable system clock frequency.
JP5 is a 6-pin jumpers which determine the system clock frequency 66 MHz to 133 MHz. and
JP6 is a 8-pin jumper which determine the processor clock ratio from 3.5X to 8X.
Several hardware settings are made through the use of jumper caps to connect jumper pins on
the main board. The jumper's pin 1 on main board will be on the top or on the left when hold-
ing the main board with the keyboard connector away from yourself.
Jumpers with two pins will be shown as for Close (On) and for Open (Off).
To connect the pins, simply place a plastic jumper cap over the two pins.
CPU Clock Speed and ratio Selection - JP5 and JP6
Figure 2-4 shows the position of JP5 and JP6 on the mainboard.
Table 2-1 shows adjustable System clock
on jumper JP5.
Table 2-2, 2-3 and 2-4 shows adjustable
CPU Clock Ratios on jumper group JP6.
System Clock JP5
66 MHz
75 MHz
83 MHz
100 MHz
103 MHz
112 MHz
133 MHz
Table 2-1
Table 2-2
Multiplier JP6
(100)
MHz
3.5X 350
4X 400
4.5X 450
5X 500
Table 2-4
Table 2-3
Multiplier JP6
(66)
MHz
4.5X 300
5X 333
5.5X 366
6X 400
Figure 2-3