Intel B940 Datasheet Page 109

  • Download
  • Add to my manuals
  • Print
  • Page
    / 360
  • Table of contents
  • BOOKMARKS
  • Rated. / 5. Based on customer reviews
Page view 108
Datasheet, Volume 2 109
Processor Configuration Registers
2.8.54 DDRMPLL1—DDR PLL BIOS Register
This register is for DDR PLL register programming.
B/D/F/Type: 0/0/0/MCHBAR
Address Offset: 2C20–2C22h
Reset Value: 00000Ch
Access: RO, RW, RW-S
Bit Attr
Reset
Value
Description
23:12 RO 00b Reserved
11 RW-S 0b
Alternative VCO Select (VCOSEL)
0 = Use VCO A
1 = Use VCO B
VCO A is recommended Default value.
10 RW-S 0b
Post Divide For DDR 800 Mode (DIVSEL)
Post Divider value 1 versus 2.
0 = Divide by 1
1 = Divide by 2
Only DRR 800 uses the additional divide by 2 due to the increased VCO speed
used by DRR 800 mode.
9:8 RW-S 0b Reserved
7RO 0bReserved
6:1 RW 000110b
Feedback Divider Ratio[6:1] (FBRATIO)
Encoding for bits 7:0 Data edge rate in MHz
0Ch = 800 MHz
10h = 1066 MHz
14h = 1333 MHz
0RO 0b
Feedback Divider Ratio[0] (FBRATIONLSB)
FB ratios are always even so the LSB is not needed.
A write to this bit will be dropped; will have no effect.
Page view 108
1 2 ... 104 105 106 107 108 109 110 111 112 113 114 ... 359 360

Comments to this Manuals

No comments