SC2200 NSC [National Semiconductor], SC2200 Datasheet - Page 97

• Manufacturer Part Number: SC2200
• Description: Thin Client On a Chip
• Manufacturer: NSC [National Semiconductor]

Revision 3.0
General Configuration Block
Offset 13h-17h
Offset 18h-1Bh
Offset 1Eh-1Fh
This register controls the configuration of the core clock multiplier and the reference clocks.
31:24
23:19
18:11
15:14
11:10
10:7
5:0
9:8
7:4
3:0
Bit
13
12
2
1
0
6
Description
FM1SD (Shut Down PLL4).
0: PLL4 is enabled.
1: PLL4 is shutdown, unless internal Fast-PCI clock is strapped to 48 MHz.
C48MD (Disable SuperI/O and USB Clock).
0: USB and SuperI/O clock is enabled.
1: USB and SuperI/O clock is disabled.
Reserved. Write as read.
MFFC (MFF Counter Value).
Fvco
OSCCLK = 27 MHz
Reserved. Write as read.
MFBC (MFB Counter Value).
Fvco
OSCCLK = 27 MHz
Reserved. Write as read
Reserved. Must be set to 0.
MOC (MO Counter Value).
Fvco
OSCCLK = 27 MHz
Reserved.
Reserved. Must be set to 0.
Reserved. Must be set to 0.
Reserved.
FPCICK (Internal Fast-PCI Clock). (Read Only) Reflects the internal Fast-PCI clock and is the input to the GX1 module
that is used to generate the core clock. These bits reflect the value of strap pins CLKSEL[1:0].
00: 33.3 MHz
01: 48 MHz
10: 66.7 MHz
11: 33.3 MHz
Reserved.
MVAL (Multiplier Value). This 4-bit value controls the multiplier in ADL. The value is set according to the Maximum Clock
Multiplier bits of the MCCM register (Offset 10h). The multiplier value should never be written with a multiplier which is differ-
ent from the multiplier indicated in the MCCM register.
0100: Multiply by 4
0101: Multiply by 5
0110: Multiply by 6
0111: Multiply by 7
1000: Multiply by 8
1001: Multiply by 9
1010: Multiply by 10
Other: Reserved
= OSCCLK * MFBC / (MFFC * MOC)
= OSCCLK * MFBC / (MFFC * MOC)
= OSCCLK * MFBC / (MFFC * MOC)
Table 3-8. Clock Generator Configuration (Continued)
Core Clock Frequency Control Register - CCFC (R/W)
PLL3 Configuration Register - PLL3C (R/W)
(Continued)
Reserved - RSVD
97
Reset Value: Strapped Value
Reset Value: E1040005h
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