ATMEga64L ATMEL Corporation, ATMEga64L Datasheet - Page 338

• Manufacturer Part Number: ATMEga64L
• Description: 8-bit AVR Microcontroller with 64K Bytes In-System Programmable Flash
• Manufacturer: ATMEL Corporation

Table 142. External Data Memory Characteristics, 2.7 - 5.5 Volts, No Wait-state (Continued)
Notes:
Table 143. External Data Memory Characteristics, 2.7 - 5.5 Volts, SRWn1 = 0, SRWn0 = 1
Table 144. External Data Memory Characteristics, 2.7 - 5.5 Volts, SRWn1 = 1, SRWn0 = 0
Table 145. External Data Memory Characteristics, 2.7 - 5.5 Volts, SRWn1 = 1, SRWn0 = 1
338
13
14
15
16
0
10
12
15
16
0
10
12
15
16
0
10
12
14
15
16
Symbol
t
t
t
t
Symbol
1/t
t
t
t
t
Symbol
1/t
t
t
t
t
Symbol
1/t
t
t
t
t
t
DVWL
WHDX
DVWH
WLWH
RLDV
RLRH
DVWH
WLWH
RLDV
RLRH
DVWH
WLWH
RLDV
RLRH
WHDX
DVWH
WLWH
1. This assumes 50% clock duty cycle. The half period is actually the high time of the external clock, XTAL1.
2. This assumes 50% clock duty cycle. The half period is actually the low time of the external clock, XTAL1.
CLCL
CLCL
CLCL
ATmega64(L)
Parameter
Data Setup to WR Low
Data Hold After WR High
Data Valid to WR High
WR Pulse Width
Parameter
Oscillator Frequency
Read Low to Data Valid
RD Pulse Width
Data Valid to WR High
WR Pulse Width
Parameter
Oscillator Frequency
Read Low to Data Valid
RD Pulse Width
Data Valid to WR High
WR Pulse Width
Parameter
Oscillator Frequency
Read Low to Data Valid
RD Pulse Width
Data Hold After WR High
Data Valid to WR High
WR Pulse Width
Min
105
235
250
235
Min
485
500
485
Min
735
750
735
Min
735
485
750
735
4 MHz Oscillator
4 MHz Oscillator
4 MHz Oscillator
4 MHz Oscillator
Max
Max
Max
Max
440
690
690
0.5t
1.0t
2.0t
1.0t
2.0t
2.0t
3.0t
3.0t
3.0t
3.0t
1.0t
2.0t
3.0t
3.0t
CLCL
Min
Min
Min
Min
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
CLCL
0.0
0.0
0.0
Variable Oscillator
Variable Oscillator
Variable Oscillator
Variable Oscillator
CLCL
CLCL
CLCL
CLCL
-20
-15
-15
-15
-15
-15
-15
-15
-15
-15
(1)
2.0t
3.0t
3.0t
Max
Max
Max
Max
CLCL
CLCL
CLCL
8
8
8
-60
-60
-60
2490G–AVR–03/04
Unit
ns
ns
ns
ns
Unit
MHz
ns
ns
ns
ns
Unit
MHz
ns
ns
ns
ns
Unit
MHz
ns
ns
ns
ns
ns