![Motorola SPX3BUM/D Скачать руководство пользователя страница 11](http://html.mh-extra.com/html/motorola/spx3bum-d/spx3bum-d_user-manual_243945011.webp)
MOTOROLA
11
3.1.6 SSCLK
The spread-spectrum enable (“SSCLK”) switch allows the user to enable and evaluate the spread-spectrum
clock generator (SSCG) option. If enabled, the SSCG modulates the PCI base clock frequency by a
selectable amount (see Section 3.1.7).
NOTE: The Sandpoint system is not guaranteed to operate if the SSCLK switch is set; this is for testing
purposes only.
3.1.7 SSRNG
The spread-spectrum range (“SSRNG”) switch allows the user to change the amount of modulation applied
to the PCI clock signals if the SSCG is enabled (see Section 3.1.6).
3.1.8 PSON
The “PSON” switch allows the user to force the system to power up whenever AC power is applied to the
system power supply. Normally, the system power is controlled with the APC in the SuperIO chip, and
power is controlled through the chassis switch, motherboard pushbutton, or APC under software control. If
PSON is selected, the system remains on until external power is removed.
Table 7. Sandpoint 3 SSCLK Switch
SSCLK
Definition
Notes
SW1-6
On (right)
PCI clocks are modulated by -1.25% or -3.75%.
Use for testing.
Off (left)
Normal PCI clocks.
Normal mode.
Table 8. Sandpoint 3 SSRNG Switch
SSRNG
Definition
Notes
SW1-7
On (right)
-3.75% modulation:
66 MHz PCI:63.5 ... 66.0 MHz
33 MHz PCI:31.8 ... 33.0 MHz
Normal mode.
Off (left)
-1.25% modulation:
66 MHz PCI:65.2 ... 66.0 MHz
33 MHz PCI:32.6 ... 33.0 MHz
Table 9. Sandpoint 3 PSON Switch
PSON
Definition
Notes
SW1-8
On (right)
Force power on always.
Normal mode.
Off (left)
Normal power control mode