Ac Electrical Specifications-External Master Internal Synchronous Read/Write Cycles - Motorola MC68302 User Manual

6.11 AC ELECTRICAL SPECIFICATIONS—EXTERNAL MASTER
INTERNAL SYNCHRONOUS READ/WRITE CYCLES
(see Figure 6-10, Figure 6-11, and Figure 6-12)
Num.
110 Address Valid to AS Low
111 AS Low to Clock High
112 Clock Low to AS High
113 AS High to Address Hold Time on Write
114 AS Inactive Time
115 UDS/LDS Low to Clock High (see Note 2)
116 Clock Low to UDS/LDS High
117 R/W Valid to Clock High (see Note 2)
118 Clock High to R/W High
119 AS Low to IAC High
120 AS High to IAC Low
121 AS Low to DTACK Low (0 Wait State)
122 Clock Low to DTACK Low (1 Wait State)
123 AS High to DTACK High
124 DTACK High to DTACK High Impedance
125 Clock High to Data-Out Valid
126 AS High to Data High Impedance
127 AS High to Data-Out Hold Time
128 AS High to Address Hold Time on Read
129 UDS/LDS Inactive Time
130 Data-In Valid to Clock Low
131 Clock Low to Data-In Hold Time
NOTES:
1. Synchronous specifications above are valid only when SAM = 1 in the SCR.
2. It is required that this signal not be asserted prior to the previous rising CLKO edge (i.e., in the previous clock
cycle). It must be recognized by the IMP no sooner than the rising CLKO edge shown in the diagram.
MOTOROLA
Characteristic
MC68302 USER'S MANUAL
16.67 MHz
Symbol Min Max Min
t
15 — 12
AVASL
t
30 — 25
ASLCH
t
— 45 —
CLASH
t
0 —
ASHAH
t
1 —
ASH
t
40 — 33
SLCH
t
— 45 —
CLSH
t
30 — 25
RWVCH
t
— 45 —
CHRWH
t
— 40 —
ASLIAH
t
— 40 —
ASHIAL
t
— 45 —
ASLDTL
t
— 30 —
CLDTL
t
— 45 —
ASHDTH
t
— 15 —
DTHDTZ
t
— 30 —
CHDOV
t
— 45 —
ASHDZ
t
0 —
ASHDOI
t
0 —
ASHAI
t
1 —
SH
t
30 — 25
CLDIV
t
15 — 12
CLDIH
Electrical Characteristics
20 MHz 25 MHz
Max Min Max
— 10 —
— 20 —
40 — 30
0 — 0 —
1 — 1 —
— 27 —
40 — 30
— 20 —
40 — 30
35 — 27
35 — 27
40 — 30
25 — 20
40 — 30
15 — 10
25 — 20
40 — 30
0 — 0 —
0 — 0 —
1 — 1 —
— 20 —
— 10 —
Unit
ns
ns
ns
ns
clk
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
ns
clk
ns
ns
6-19