Intel
®
81341 and 81342—Peripheral Bus Interface Unit
Intel
®
81341 and 81342 I/O Processors
Developer’s Manual
December 2007
716
Order Number: 315037-002US
illustrates a burst read cycle example for a 120 ns Flash device. This
example is illustrating a burst of two bytes or words. The PBI is capable of bursting up
to four bytes or words. The number of wait states used for address-to-data and data-
to-data are provided by the Address-to-Data Wait States and the Data-to-Data Wait
States field in PBBARx respectively.
for the programmable address-to-data, data-to-data, and recovery
wait states. These numbers are based on a 66 MHz internal clock for the PBI interface.
Figure 110. 120 ns Flash Burst Read Cycle
A[24:03]
A[02:00]
Ta1
Tw1
Tw4
Td2
Tr1
Tr4
POE #
PWE #
PCEx #
Tw1
Tw8
Td2
D[15:00]
D_in
D_ in
Ti/Ta
Ta2
Td1
Td1
B6270-01
Table 432. Flash Wait State Profile Programming
Flash Speed Address-to-Data Wait States Data-to-Data Wait States
Recovery Wait States
<= 55 ns
4
4
1
<= 120 ns
8
4
4
<= 150 ns
12
4
4
Notes:
1.
Each Wait State represents a 15 ns period based on a 66 MHz clock. Refer to the appropriate Flash
device datasheets for programming accurate wait state numbers.
2.
Data-to-Data wait states are used for burst reads.