
Functional Description and Application Information
MC9328MXS Technical Data, Rev. 3
24
Freescale Semiconductor
4.4.1
DTACK Signal Description
The DTACK signal is the external input data acknowledge signal. When using the external DTACK signal
as a data acknowledge signal, the bus time-out monitor generates a bus error when a bus cycle is not
terminated by the external DTACK signal after 1022 HCLK counts have elapsed. Only the CS5 group
supports DTACK signal function when the external DTACK signal is used for data acknowledgement.
4.4.2
DTACK Signal Timing
Figure 6 through
Figure 9 show the access cycle timing used by chip-select 5. The signal values and units
of measure for this figure are found in the associated tables.
4a
Clock1 rise to Output Enable Valid
2.32
2.62
6.85
2.3
2.6
6.8
ns
4b
Clock1 rise to Output Enable Invalid
2.11
2.52
6.55
2.1
2.5
6.5
ns
4c
Clock1 fall to Output Enable Valid
2.38
2.69
7.04
2.3
2.6
6.8
ns
4d
Clock1 fall to Output Enable Invalid
2.17
2.59
6.73
2.1
2.5
6.5
ns
5a
Clock1 rise to Enable Bytes Valid
1.91
2.52
5.54
1.9
2.5
5.5
ns
5b
Clock1 rise to Enable Bytes Invalid
1.81
2.42
5.24
1.8
2.4
5.2
ns
5c
Clock1 fall to Enable Bytes Valid
1.97
2.59
5.69
1.9
2.5
5.5
ns
5d
Clock1 fall to Enable Bytes Invalid
1.76
2.48
5.38
1.7
2.4
5.2
ns
6a
Clock1 fall to Load Burst Address Valid
2.07
2.79
6.73
2.0
2.7
6.5
ns
6b
Clock1 fall to Load Burst Address Invalid
1.97
2.79
6.83
1.9
2.7
6.6
ns
6c
Clock1 rise to Load Burst Address Invalid
1.91
2.62
6.45
1.9
2.6
6.4
ns
7a
Clock1 rise to Burst Clock rise
1.61
2.62
5.64
1.6
2.6
5.6
ns
7b
Clock1rise to Burst Clock fall
1.61
2.62
5.84
1.6
2.6
5.8
ns
7c
Clock1 fall to Burst Clock rise
1.55
2.48
5.59
1.5
2.4
5.4
ns
7d
Clock1 fall to Burst Clock fall
1.55
2.59
5.80
1.5
2.5
5.6
ns
8a
Read Data setup time
5.54
–
5.5
–
ns
8b
Read Data hold time
0
–
0
–
ns
9a
Clock1 rise to Write Data Valid
1.81
2.72
6.85
1.8
2.7
6.8
ns
9b
Clock1 fall to Write Data Invalid
1.45
2.48
5.69
1.4
2.4
5.5
ns
9c
Clock1 rise to Write Data Invalid
1.63
–
1.62
–
ns
10a
DTACK setup time
2.52
–
2.5
–
ns
1 Clock refers to the system clock signal, HCLK, generated from the System DPLL
Table 12. EIM Bus Timing Parameter Table (Continued)
Ref No.
Parameter
1.8 ± 0.1 V
3.0 ± 0.3 V
Unit
Min
Typical
Max
Min
Typical
Max