NEC PowerMate 466M, Руководство по обслуживанию

Страница: 55 / 184

Setup and Operation 2-25
Table Section 2-14 shows the factory settings of the system configuration jumpers and ex-
plains the function of each position.
Table Section 2-14 System Configuration Jumpers
Jumper Function Factory Setting
JP1 Clear CMOS jumper – Reset CMOS to factory settings.
1–2 Shorted: Clears and resets CMOS to factory settings
2–3 Shorted: Normal operation
2–3 Shorted
JP2 Processor upgrade jumper – Selects write-through or write-back
mode.
1–2 Shorted: Selects write-through mode
2–3 Shorted: Selects write-back mode (future processors)
1–2 Shorted
JP3 SX processor jumper – Selects SX or DX processor.
1–2 Shorted: DX based systems
2–3 Shorted: SX based systems
1–2 Shorted (466D,
466M, 4100M)
2–3 Shorted (433D)
JP6 CPU clock select jumper – Sets the input clock speed to the
CPU.
1–2 Shorted: CPU clock speed is 33 MHz
2–3 Shorted: CPU clock speed is 25 MHz
1–2 Shorted
JP9A Serial port 1 interrupt jumpers – Selects the interrupt for serial
port 1.
1–2 Shorted: IRQ4
3–4 Shorted: IRQ10
1–2 Shorted
JP9B Serial port 2 interrupt jumpers – Selects the interrupt for serial
port 2.
5–6 Shorted: IRQ3
7–8 Shorted: IRQ11
5–6 Shorted
JP9C Printer port interrupt jumpers – Selects the interrupt for the
parallel port.
9–10 Shorted: IRQ7
11–12 Shorted: IRQ5
9–10 Shorted
JP9D Printer port DMA jumpers – Selects the DMA channel for the
parallel port.
13–14 Shorted: DMA channel 1
15–16 Shorted: DMA channel 3
15–16 Shorted