HD6412240 RENESAS [Renesas Technology Corp], HD6412240 Datasheet - Page 213

• Manufacturer Part Number: HD6412240
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family / H8S/2200 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

(3) Relationship between Chip Select (CS
Depending on the system's load conditions, the RD signal may lag behind the CS signal. An
example is shown in figure 6.22.
In this case, with the setting for no idle cycle insertion (a), there may be a period of overlap
between the bus cycle A RD signal and the bus cycle B CS signal.
Setting idle cycle insertion, as in (b), however, will prevent any overlap between the RD and CS
signals.
In the initial state after reset release, idle cycle insertion (b) is set.
Address bus
CS (area A)
CS (area B)
RD
Possibility of overlap between
CS (area B) and RD
Figure 6.22 Relationship between Chip Select (CS
(a) Idle cycle not inserted
T
1
Bus cycle A
(ICIS1 = 0)
T
2
T
3
Bus cycle B
T
1
T
2
CS
CS) Signal and Read (RD
CS
Address bus
CS (area A)
CS (area B)
RD
Rev.3.00 Mar. 26, 2007 Page 171 of 772
T
RD
RD) Signal
CS) and Read (RD
CS
CS
RD
1
Bus cycle A
(b) Idle cycle inserted
T
(Initial value ICIS1 = 1)
2
Section 6 Bus Controller
T
3
REJ09B0355-0300
RD)
RD
RD
T
I
Bus cycle B
T
1
T
2