SH7032 Datasheet, PDF (169/687 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

Section 8 Bus State Controller (BSC)
Wait states
set in WCR3
Wait state Wait
from WAIT states set
signal input in WCR3
T1
T_LW1
T_LW2
T_W
T_LW3
CK
A21–A0
CSn
RD
Read
AD15–AD0
WRH, WRL
Write
AD15–AD0
WAIT
Figure 8.14 Wait State Timing for External Memory Space Access (1 State Plus Long Wait
State (When Set to Insert 3 States) Plus Wait States from WAIT Signal)
For CPU write cycles and DMAC dual mode write cycles to external memory space, the number
of states and wait state insertion cannot be controlled by WCR1. In areas 1, 3, 4, 5, and 7, the
WAIT signal is sampled and the number of states is 2 plus the number of wait states set by the
WAIT signal (figure 8.13). In areas 0, 2 and 6, the number of states is 1 state plus the number of
long wait states plus the number of wait states set by the WAIT signal (figure 8.14). Do not write
0 in bits 7–2 and 0 of WCR1; only write 1. When area 1 is being used as external memory space,
do not write 0 in bit 1 (WW1); always write 1.
Rev. 7.00 Jan 31, 2006 page 143 of 658
REJ09B0272-0700