h8s-2158 Renesas Electronics Corporation., h8s-2158 Datasheet - Page 192

• Manufacturer Part Number: h8s-2158
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

Section 6 Bus Controller
6.7.4
With memory card interface, there are two ways of inserting wait states: Program wait insertion
and pin wait insertion using the CPWAIT pin.
Program Wait Mode: A specified number of wait states T
and T
and WC20 bits in WSCR2.
Pin Wait Mode: A specified number of wait states T
state when accessing the CF expansion area according to the settings in the WC22, WC21, and
WC20 bits. If the CPWAIT pin is low at the falling edge of in the last T
state is inserted. If the CPWAIT pin is held low, T
however, that T
is specified.
Figure 6.19 shows an example of wait state insertion timing.
Rev. 3.00 Jan 25, 2006 page 140 of 872
REJ09B0286-0300
Read
Write
CPCS1, CPCS2
Figure 6.19 Access Timing Example in Memory Card Mode (Wait State Insertion by
Address bus
3
D15 to D0
D15 to D0
state when accessing the CF expansion area according to the settings in the WC22, WC21,
CPWAIT
CPWE
Wait Control
CPOE
W
state insertion by the CPWAIT pin is not performed unless program wait mode
T
1
By program wait
Program Wait and CPWAIT
T
W
T
W
By CPWAIT pin
Valid
W
states are inserted until it goes high. Note,
CPWAIT Pin)
CPWAIT
CPWAIT
W
can be inserted between the T
T
W
W
can be inserted between the T
T
2
2
or T
W
Valid
state, another T
T
3
2
state and T
2
state
W
3