PD488588FF Datasheet, PDF (12/79 Pages) Elpida Memory – 288M bits Direct Rambus DRAM for High Performance Solution

µPD488588FF-C80-40
3. Field Encoding Summary
Table 3-1 shows how the six device address bits are decoded for the ROWA and ROWR packets. The DR4T and
DR4F encoding merges a fifth device bit with a framing bit. When neither bit is asserted, the device is not selected.
Note that a broadcast operation is indicated when both bits are set. Broadcast operation would typically be used for
refresh and power management commands. If the device is selected, the DM (DeviceMatch) signal is asserted and
an ACT or ROP command is performed.
DR4T
1
0
1
0
Table 3-1 Device Field Encodings for ROWA Packet and ROWR Packet
DR4F
1
1
0
0
Device Selection
All devices (broadcast)
One device selected
One device selected
No packet present
Device Match signal (DM)
DM is set to 1
DM is set to 1 if {DEVID4..DEVID0} == {0, DR3..DR0} else DM is set to 0
DM is set to 1 if {DEVID4..DEVID0} == {1, DR3..DR0} else DM is set to 0
DM is set to 0
Table 3-2 shows the encodings of the remaining fields of the ROWA and ROWR packets. An ROWA packet is
specified by asserting the AV bit. This causes the specified row of the specified bank of this device to be loaded into
the associated sense amps.
An ROWR packet is specified when AV is not asserted. An 11 bit opcode field encodes a command for one of the
banks of this device. The PRER command causes a bank and its two associated sense amps to precharge, so
another row or an adjacent bank may be activated.
The REFA (refresh-activate) command is similar to the ACT command, except the row address comes from an
internal register REFR, and REFR is incremented at the largest bank address. The REFP (refresh-precharge)
command is identical to a PRER command.
The NAPR, NAPRC, PDNR, ATTN, and RLXR commands are used for managing the power dissipation of the
RDRAM and are described in more detail in “23. Power State Management”. The TCEN and TCAL commands are
used to adjust the output driver slew rate and they are described in more detail in “25. Current and Temperature
Control”.
Table 3-2 ROWA Packet and ROWR Packet Field Encodings
DM AV
ROP10..ROP0 Field
Name
Note1
10 9 8 7 6 5 4 3 2 : 0
Command Description
0 — — — — — — — — — --- —
1 1 Row address
ACT
No operation.
Activate row R8..R0 of bank BR4..BR0 of device and move device to
ATTN . ^Note2
1 0 1 1 0 0 0 x ^Note3 x x 000 PRER
Precharge bank BR4..BR0 of this device.
1 0 0 0 0 1 1 0 0 x 000 REFA
Refresh (activate) row REFR8..REFR0 of bank BR3..BR0 of device.
Increment REFR if BR4..BR0=11111 (see Figure 24-1).
1 0 1 0 1 0 1 0 0 x 000 REFP
Precharge bank BR4..BR0 of this device after REFA (see Figure 24-1).
1 0 x x 0 0 0 0 1 x 000 PDNR Move this device into the powerdown (PDN) power state (see figure 23-3).
1 0 x x 0 0 0 1 0 x 000 NAPR Move this device into the nap (NAP) power state (see Figure 23-3).
1 0 x x 0 0 0 1 1 x 000 NAPRC Move this device into the nap (NAP) power state conditionally.
1 0 x x x x x x x 0 000 ATTN ^Note2 Move this device into the attention (ATTN) power state (see Figure 23-1).
1 0 x x x x x x x 1 000 RLXR
Move this device into the standby (STBY) power state (see Figure 23-2).
1 0 0 0 0 0 0 0 0 x 001 TCAL
Temperature calibrate this device (see figure 25-2).
1 0 0 0 0 0 0 0 0 x 010 TCEN Temperature calibrate/enable this device (see Figure 25-2).
1 0 0 0 0 0 0 0 0 0 000 NOROP No operation.
Notes 1. The DM (Device Match signal) value is determined by the DR4T, DR4F, DR3..DR0 field of the ROWA and ROWR packets.
See Table 3-1.
2. The ATTN command does not cause a RLX-to-ATTN transition for a broadcast operation (DR4T/DR4F=1/1).
3. An “x” entry indicates which commands may be combined. For instance, the three commands PRER/NAPRC/RLXR may
be specified in one ROP value (011000111000).
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Data Sheet E0251N20 (Ver. 2.0)