AMD SC3200 manual Bit Description GXBASE+8408h-840Bh, Mcbankcfg R/W, Rsvd Reserved. Write as 0070h

Models: SC3200

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32581CArchitecture Overview

Table 2-2. SC3200 Memory Controller Registers (Continued)

Bit

Description

 

 

 

 

 

 

 

 

 

GX_BASE+8408h-840Bh

 

MC_BANK_CFG (R/W)

Reset Value: 41104110h

 

 

 

 

 

31:16

RSVD (Reserved). Write as 0070h

 

 

 

 

 

 

 

 

15

RSVD (Reserved). Write as 0.

 

 

 

 

 

14

SODIMM_MOD_BNK (SODIMM Module Banks - Banks 0 and 1). Selects number of module banks installed per SODIMM

 

for SODIMM:

 

 

 

 

 

0: 1 Module bank (Bank 0 only)

 

 

 

 

1: 2 Module banks (Bank 0 and 1)

 

 

 

 

 

 

 

 

13

RSVD (Reserved). Write as 0.

 

 

 

 

 

12

SODIMM_COMP_BNK (SODIMM Component Banks - Banks 0 and 1). Selects the number of component banks per

 

module bank for SODIMM:

 

 

 

 

0: 2 Component banks

 

 

 

 

1: 4 Component banks

 

 

 

 

Banks 0 and 1 must have the same number of component banks.

 

 

 

 

 

 

11

RSVD (Reserved). Write as 0.

 

 

 

 

 

 

10:8

SODIMM_SZ (SODIMM Size - Banks 0 and 1). Selects the size of SODIMM:

 

 

000: 4 MB

010: 16 MB

100: 64 MB

110: 256 MB

 

 

001: 8 MB

011: 32 MB

101: 128 MB

111: 512 MB

 

 

This size is the total of both banks 0 and 1. Also, banks 0 and 1 must be the same size.

 

 

 

 

 

 

7

RSVD (Reserved). Write as 0.

 

 

 

 

 

 

6:4

SODIMM_PG_SZ (SODIMM Page Size - Banks 0 and 1). Selects the page size of SODIMM:

 

 

000: 1 KB

010: 4 KB

1xx: 16 KB

 

 

 

001: 2 KB

011: 8 KB

111: SODIMM not installed

 

 

Both banks 0 and 1 must have the same page size.

 

 

 

 

 

 

 

3:0

RSVD (Reserved). Write as 0.

 

 

 

 

 

 

 

 

 

GX_BASE+840Ch-840Fh

 

MC_SYNC_TIM1 (R/W)

Reset Value: 2A733225h

 

 

 

 

 

31

RSVD (Reserved). Write as 0.

 

 

 

 

 

30:28

LTMODE (CAS Latency). CAS latency is the delay, in SDRAM clock cycles, between the registration of a read command

 

and the availability of the first piece of output data. This parameter significantly affects system performance. Optimal setting

 

should be used. If an SODIMM is used, BIOS can interrogate EEPROM across the ACCESS.bus interface to determine this

 

value:

 

 

 

 

 

000: Reserved

010: 2 CLK

100: 4 CLK

110: 6 CLK

 

 

001: Reserved

011: 3 CLK

101: 5 CLK

111: 7 CLK

 

 

This field will not take effect until SDRAMPRG (bit 0 of MC_MEM_CNTRL1) transitions from 0 to 1.

 

 

27:24

RC (RFSH to RFSH/ACT Command Period, tRC). Minimum number of SDRAM clock between RFSH and RFSH/ACT

 

commands:

 

 

 

 

 

0000: Reserved

0100: 5 CLK

1000: 9 CLK

1100: 13 CLK

 

 

0001: 2 CLK

0101: 6 CLK

1001: 10 CLK

1101: 14 CLK

 

 

0010: 3 CLK

0110: 7 CLK

1010: 11 CLK

1110: 15 CLK

 

 

0011: 4 CLK

0111: 8 CLK

1011: 12 CLK

1111: 16 CLK

 

 

 

23:20

RAS (ACT to PRE Command Period, tRAS). Minimum number of SDRAM clocks between ACT and PRE commands:

 

0000: Reserved

0100: 5 CLK

1000: 9 CLK

1100: 13 CLK

 

 

0001: 2 CLK

0101: 6 CLK

1001: 10 CLK

1101: 14 CLK

 

 

0010: 3 CLK

0110: 7 CLK

1010: 11 CLK

1110: 15 CLK

 

 

0011: 4 CLK

0111: 8 CLK

1011: 12 CLK

1111: 16 CLK

 

 

 

 

 

 

19

RSVD (Reserved). Write as 0.

 

 

 

 

 

18:16

RP (PRE to ACT Command Period, tRP). Minimum number of SDRAM clocks between PRE and ACT commands:

 

000: Reserved

010: 2 CLK

100: 4 CLK

110: 6 CLK

 

 

001: 1 CLK

011: 3 CLK

101: 5 CLK

111: 7 CLK

 

 

 

 

 

 

15

RSVD (Reserved). Write as 0.

 

 

 

 

 

14:12

RCD (Delay Time ACT to READ/WRT Command, tRCD). Minimum number of SDRAM clock between ACT and READ/

 

WRT commands. This parameter significantly affects system performance. Optimal setting should be used:

 

000: Reserved

010: 2 CLK

100: 4 CLK

110: 6 CLK

 

 

001: 1 CLK

011: 3 CLK

101: 5 CLK

111: 7 CLK

 

 

 

 

 

 

 

 

 

 

 

 

20

 

 

 

AMD Geode™ SC3200 Processor Data Book

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AMD SC3200 manual Bit Description GXBASE+8408h-840Bh, Mcbankcfg R/W, Rsvd Reserved. Write as 0070h, MCSYNCTIM1 R/W