Device Interface Functional Overview
Ready Support
Copyright © 2002 Marvell
CONFIDENTIAL
Doc. No. MV-S300165-00, Rev. A
May 21, 2002, Preliminary
Document Classification: Proprietary Information
Page 59
Figure 25: Device Burst Write Example
6.6
Ready Support
To support devices with long or undetermined access times, the GT-64260A implements the Ready* pin on the
device interface. The Ready* pin extends the access timing parameters for Acc2First, Acc2Next, and WrLow.
In addition, the Ready* pin supports non-sampled and sampled modes. The sampled mode adds an additional
clock cycle to the access and is used to reduce the setup time of the Ready* pin.
Note
In the GT-64260A datasheet, the Ready* pin AC timing refers to the sampled mode. There is no AC timing
for the non-sampled mode. For more information, see the GT-64260A datasheet’s "AC Timing" section.
CSTiming*
AD[31:0]
BAdr[2:0]
DevRW*
Wr*
Device_addr[26:3]
DBDLast*
ALE
B1
Burst
Last
1clk
1clk
1clk
1clk
ALE2Wr
Notes:
1. * One clock setup time only if the WrHigh is larger than 1
2. ** One clock hold time only if the WrHigh is larger than 0
3. Latch depends on the latch device. Such as a discrete device
(e.g., 74373) or PLD.
B0
D1
Address
WrLow
WrHigh
1clk
1clk**
1clk*
1clk**
Address
D0
WrHigh
`
Address
T
latch