Sony AR-B1474, DX4, 486DX manual CPU Clock Select JP6 & JP9, CPU Clock Setting

AR-B1474 User¡¦s Guide

(4) CPU Clock Select (JP6 & JP9)

For different type of CPUs, the clock generator and clock divisor need to be set by JP6 and JP9. The clock base is selected by JP6, JP9 is used to select single or half clock system. We recommend that you refer the following table for setting the CPU clock.

1 2 3 JP9 1 2 3

1	2	3	1	2	3
	1X			2X

Factory Preset

Figure 3-14 JP9: CPU System Clock Multiplier Select

Pin	Definition
1-2	A
3-4	B
5-6	C

2 4 6

1 3 5

A B C

Table 3-5 JP6: CPU Base Clock

CPU Type	CPU	Base	JP9		JP6		Note
	Clock	Clock		A	B	C
DX-25, DX2-50,	25MHz	50MHz	1X	Close	Open	Open
DX4-75
DX-33, DX2-66,	33.3MHz	33.3MHz	1X	Close	Open	Close	Factory
DX4-100, 5X86-							Preset
133
DX-40, DX2-80,	40MHz	40MHz	1X	Close	Close	Open
DX4-120
DX-50	50MHZ	50MHz	1X	Close	Close	Close

Table 3-6 CPU Clock Setting

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