MEGA128CAN Datasheet, PDF (367/413 Pages) ATMEL Corporation – Microcontroller WITH 128K BYTES OF ISP FLASH AND CAN CONTROLLER

AT90CAN128
Table 146. External Data Memory Characteristics, V_CC = 2.7 - 5.5 Volts, No Wait-state
4 MHz Oscillator
Variable Oscillator
Symbol Parameter
Min.
Max.
Min.
Max.
0 1/t_CLCL
Oscillator Frequency
0.0
16
1
t_LHLL
ALE Pulse Width
235
t_CLCL – 15
2
t_AVLL
Address Valid A to ALE Low
115
0.5 t_CLCL – 10 ⁽¹⁾
3a t_{LLAX_ST}
Address Hold After ALE Low,
write access
5
5
3b t_{LLAX_LD}
Address Hold after ALE Low,
read access
5
5
4
t_AVLLC
Address Valid C to ALE Low
115
0.5 t_CLCL – 10 ⁽¹⁾
5
t_AVRL
Address Valid to RD Low
235
1.0 t_CLCL – 15
6
t_AVWL
7
t_LLWL
Address Valid to WR Low
ALE Low to WR Low
235
1.0 t_CLCL – 15
115
130
0.5 t_CLCL – 10 ⁽²⁾
0.5 t_CLCL + 5 ⁽²⁾
8
t_LLRL
ALE Low to RD Low
115
130
0.5 t_CLCL – 10 ⁽²⁾
0.5 t_CLCL + 5 ⁽²⁾
9
t_DVRH
Data Setup to RD High
45
45
10 t_RLDV
Read Low to Data Valid
190
1.0 t_CLCL – 60
11 t_RHDX
Data Hold After RD High
0
0
12 t_RLRH
RD Pulse Width
235
13 t_DVWL
Data Setup to WR Low
105
1.0 t_CLCL – 15
0.5 t_CLCL – 20 ⁽¹⁾
14 t_WHDX
Data Hold After WR High
235
1.0 t_CLCL – 15
15 t_DVWH
Data Valid to WR High
250
1.0 t_CLCL
16 t_WLWH
WR Pulse Width
235
1.0 t_CLCL – 15
Notes: 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.
Unit
MHz
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
4250E–CAN–12/04
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