Presence Detect - DEC Digital Alpha VME 4/224 User Manual

Table 9–4 Presence Detect
Bit PD Bit Description
<3:0> PD 4-1
PD Bits
4 3 2 1
0 1 0 0
0 1 0 1
1 0 1 1
1 0 1 1
<4> PD 5 Controls data mode access, according to the following values:
PD5
0
1
<6:5> PD 7-6 Controls speed, according to the following values:
PD 7
0
1
1
0
0
<7> PD 8 Used to define memory DIMM configuration (see Table 9–6).
Configuration DRAM
(Parity/ECC) Organization
1M x 72/80 1M x 4/16
2M x 72/80 1M x 4/16
4M x 72 4M x 4
4M x 80 4M x 4
Definition
Fast page
Fast page with EDO
PD 6 Speed
1 80 ns
0 70 ns
1 60 ns
0 50 ns
1 40 ns
RE CE Refresh
Address Address Periods (ms)
Normal Slow
10 10 16
10 10 16
12 11 64
12 10 64
Nbus 9–11
128
128
256
256