P30-65nm
11.2
Read Configuration Register (RCR) (Easy BGA)
The RCR is a 16-bit read/write register used to select bus-read mode (synchronous or
asynchronous), and to configure synchronous burst read characteristics of the device.
To modify RCR settings, use the Configure Read Configuration Register command (see
Section 6.2, “Device Command Bus Cycles” on page 20).
RCR contents can be examined using the Read Device Identifier command, and then
reading from offset 0x05 (see Section 7.2, “Read Device Identifier” on page 22).
Upon power-up or exit from reset, the RCR defaults to asynchronous mode.
The RCR is shown in Table 13. The following sections describe each RCR bit function.
Table 13: Read Configuration Register Description (Sheet 1 of 2)
Read Configuration Register (RCR)
WAIT
Delay
Burst
Wrap
Read
Mode
WAIT
Burst
Seq
CLK
Latency Count
LC[3:0]
RES
RES
RES
Burst Length
Polarity
Edge
RM
15
Bit
WP
10
R
9
WD
8
BS
7
CE
6
R
5
R
4
BW
3
BL[2:0]
1
14
13
12
11
2
0
Name
Description
0 = Synchronous burst-mode read
1 = Asynchronous page-mode read (default)
15
Read Mode (RM)
0011 =Code 3
0100 =Code 4
0101 =Code 5
0110 =Code 6
0111 =Code 7
1000 =Code 8
1001 =Code 9
14:11
Latency Count (LC[3:0])
1010 =Code 10
1011 =Code 11
1100 =Code 12
1101 =Code 13
1110 =Code 14
1111 =Code 15 (default)
(Other bit settings are reserved)
0 =WAIT signal is active low (default)
1 =WAIT signal is active high
WAIT Polarity (WP)
10
9
Reserved (R)
Default “0”, Non-changeable
0 =WAIT deasserted with valid data
8
WAIT Delay (WD)
Burst Sequence (BS)
1 =WAIT deasserted one data cycle before valid data (default)
7
Default “0”, Non-changeable
Clock Edge (CE)
Reserved (R)
0 = Falling edge
1 = Rising edge (default)
6
5:4
Reserved bits should be cleared (0)
Datasheet
35
Sept 2012
OrderNumber:208042-06
MICRON [ MICRON TECHNOLOGY ]
