Data Sheet E0094N20 (Ver. 2.0)

6

MC-4R256FKE6D

(2/2)

Signal

I/O

Type

Description

RSCK

I

Serial clock input. Clock source used to read from and write to the RDRAM

control registers.

SA0

I

Serial Presence Detect Address 0.

SA1

I

Serial Presence Detect Address 1.

SA2

I

Serial Presence Detect Address 2.

SCL

I

Serial Presence Detect Clock.

SDA

I/O

Serial Presence Detect Data (Open Collector I/O).

SIN

I/O

Serial I/O for reading from and writing to the control registers. Attaches to SIO0

of the first RDRAM on the module.

SOUT

I/O

Serial I/O for reading from and writing to the control registers. Attaches to SIO1

of the last RDRAM on the module.

—

—

SPD Voltage. Used for signals SCL, SDA, SWP, SA0, SA1 and SA2.

SWP

I

Serial Presence Detect Write Protect (active high). When low, the SPD can be

written as well as read.

—

—

CMOS I/O Voltage. Used for signals CMD, SCK, SIN, SOUT.

—

—

Supply voltage for the RDRAM core and interface logic.

—

—

Logic threshold reference voltage for RSL signals.