Compaq Deskpro 4000 Technical Reference Manual page 44

Chapter 3 Processor/Memory Subsystem
Table 3–5. SPD Address Map (SDRAM DIMM)
Byte Description
0 No. of Bytes Written Into EEPROM
1 Total Bytes (#) In EEPROM
2 Memory Type
3 No. of Row Addresses On DIMM
4 No. of Column Addresses On DIMM
5 No. of Module Banks On DIMM
6, 7 Data Width of Module
8 Voltage Interface Standard of DIMM
9 Cycletime @ Max CAS Latency (CL)
10 Access From Clock
11 Config. Type (Parity, Nonparity, etc.)
12 Refresh Rate/Type
13 Width, Primary DRAM
14 Error Checking Data Width
15 Min. Clock Delay
16 Burst Lengths Supported
17 No. of Banks For Each Mem. Device
18 CAS Latencies Supported
19 CS# Latency
20 Write Latency
21 DIMM Attributes
22 Memory Device Attributes
23 Min. Clock Cycle Time at CL X-1
24 Max. Acc. Time From CLK at CL X-1
25 Min. Clock Cycle Time at CL X-2
26 Max. Acc. Time From CLK at CL X-2
27 Min. Row Precharge Time
28 Min. Row Active To Row Active Delay
29 Min. RAS to CAS Delay
30, 31 Reserved
32..61 Superset Data For Future Use
NOTES:
[1] Programmed as 128 bytes by the DIMM's OEM
[2] Must be programmed to 256 bytes.
[3] High order bit defines redundant addressing: if set (1), highest order RAS# address must be
re-sent as highest order CAS# address.
[4] Refer to memory manufacturer's datasheet
[5] MSb is Self Refresh flag. If set (1), assembly supports self refresh.
[6] Back-to-back random column addresses.
[7] Field format proposed to JEDEC but not defined as standard at publication time.
[8] Field specified as optional by JEDEC but required by this system.
[9] Field format proposed to JEDEC. This system requires that the DIMM's EEPROM have this
space available for reads/writes.
3-8 Compaq Deskpro 4000 and 6000 Personal Computers
featuring the Pentium II Processor
Table 3-5.
SPD Address Map (SDRAM DIMM)
Notes
[1]
[2]
[3]
[4]
[4]
[4] [5]
[6]
[4]
[4]
[4]
[4]
[7]
[7]
[7]
[7]
[7]
[7]
[7]
First Edition - October 1997
Byte Description
62 SPD Revision
63 Checksum Bytes 0-62
64-71 JEP-106E ID Code
72 DIMM OEM Location
73-90 OEM's Part Number
91, 92 OEM's Rev. Code
93, 94 Manufacture Date
95-98 OEM's Assembly S/N
99-125 OEM Specific Data
126, 127 Reserved
128-135 Sys. Integrator's ID
136-150 Sys. Integrator's P/N
151-152 Sys. Integrator's D/C
153-165 Sys. Integrator's S/N
166 Chksm Bytes 128-165
167-189 Top Level Sys. S/N
190-221 Avaiable for use
222 Chksm Bytes 167-221
223-253 Available for use
254 Chksm Bytes 223-253
255 Chksm Byes 0-128
Notes
[7]
[8]
[8]
[8]
[8]
[8]
[8]
[8]
[9]
[9]
[9]
[9]
[9]
[9]
[9]
[9]
[9]
[9]
[9]