Data Sheet M14837EJ3V0DS00

13

µµµµPD488448 for Rev. P

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.

Table 3-1 Device Field Encodings for ROWA Packet and ROWR Packet

DR4T

DR4F

Device Selection

Device Match signal (DM)

1

1

All devices (broadcast)

DM is set to 1

0

1

One device selected

DM is set to 1 if {DEVID4..DEVID0} == {0, DR3..DR0} else DM is set to 0

1

0

One device selected

DM is set to 1 if {DEVID4..DEVID0} == {1, DR3..DR0} else DM is set to 0

0

0

No packet present

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

Command Description

Note1

10 9876

5

4

3

2 : 0

0

—

—————

—

— —

---

—

No operation.

1

1

Row address

ACT

Activate row R8..R0 of bank BR4..BR0 of device and move device to

ATTN

10

1

1000

x

x

000 PRER

Precharge bank BR4..BR0 of this device.

1

0

000

1

1

0

0

x

000 REFA

Refresh (activate) row REFR8..REFR0 of bank BR4..BR0 of device.

Increment REFR if BR4..BR0=11111 (see Figure 24-1).

10

10

10

1

0

0

x

000 REFP

Precharge bank BR4..BR0 of this device after REFA (see Figure 24-1).

1

0

x

x

000

0

1

x

000 PDNR

Move this device into the powerdown (PDN) power state (see figure 23-3).

1

0

x

x

000

1

0

x

000 NAPR

Move this device into the nap (NAP) power state (see Figure 23-3).

1

0

x

x

000

1

1

x

000 NAPRC

Move this device into the nap (NAP) power state conditionally.

1

0

xxxxx

x

x

0

000 ATTN

Note2

Move this device into the attention (ATTN) power state (see Figure 23-1).

1

0

xxxxx

x

x

1

000 RLXR

Move this device into the standby (STBY) power state (see Figure 23-2).

1

0

00000

0

0

x

001 TCAL

Temperature calibrate this device (see figure 25-2).

1

0

00000

0

0

x

010 TCEN

Temperature calibrate/enable this device (see Figure 25-2).

1

0

00000

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 (RD4T/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).