ATMEGA128-16AU SL383 Atmel, ATMEGA128-16AU SL383 Datasheet - Page 332

• Manufacturer Part Number: ATMEGA128-16AU SL383
• Manufacturer: Atmel

332
ATmega128
Figure 159. External Memory Timing (SRWn1 = 1, SRWn0 = 0)
Figure 160. External Memory Timing (SRWn1 = 1, SRWn0 = 1)
Note:
System Clock (CLK
System Clock (CLK
DA7:0 (XMBK = 0)
DA7:0 (XMBK = 0)
1. The ALE pulse in the last period (T4-T7) is only present if the next instruction accesses the
RAM (internal or external).
DA7:0
A15:8
CPU
ALE
WR
RD
DA7:0
A15:8
CPU
ALE
)
WR
RD
Prev. addr.
Prev. data
)
Prev. addr.
Prev. data
T1
T1
1
Address
Address
4
2
5
1
T2
6
Address
Address
3a
3b
4
2
XX
7
8
5
T2
6
13
3a
3b
XX
10
7
8
13
T3
10
T3
Address
Data
12
Data
16
15
9
T4
Data
Address
12
Data
16
15
T4
9
T5
(1)
11
T5
T6
11
14
T6
14
T7
2467S–AVR–07/09