122
Example of Wait State Control Settings: A reset initializes ASTCR and WCER to H'FF and
WCR to H'F3, selecting programmable wait mode and three wait states for all areas. Software can
select other wait modes for individual areas by modifying the ASTCR, WCER, and WCR settings.
Figure 6-9 shows an example of wait mode settings.
7
6
5
4
3
2
1
0
0
0
—
0
0
—
0
1
—
0
1
—
1
0
0
1
0
0
1
1
1
1
1
1
Bit:
ASTCR H'0F:
WCER H'33:
WCR H'F3:
Area 0
Area 1
Area 2
Area 3
Area 4
Area 5
Area 6
Area 7
3-state-access area,
programmable wait mode
3-state-access area,
programmable wait mode
3-state-access area,
pin wait mode 0
3-state-access area,
pin wait mode 0
2-state-access area,
no wait states inserted
2-state-access area,
no wait states inserted
2-state-access area,
no wait states inserted
2-state-access area,
no wait states inserted
Note: Wait states cannot be inserted in areas designated for two-state access by ASTCR.
Figure 6-9 Wait Mode Settings (Example)