HD6432160 RENESAS [Renesas Technology Corp], HD6432160 Datasheet - Page 170

• Manufacturer Part Number: HD6432160
• Description: Hitachi 16-Bit Single-Chip Microcomputer
• Manufacturer: RENESAS [Renesas Technology Corp]

6.5.4
When accessing the external address space, this LSI can extend the bus cycle by inserting one or
more wait states (T
wait insertion using the :$,7 pin, and the combination of program wait and the :$,7 pin.
Program Wait Mode: A specified number of wait states T
between the T
the settings of the WC1 and WC0 bits in WSCR.
Pin Wait Mode: A specified number of wait states T
T
the WC1 and WC0 bits. If the :$,7 pin is low at the falling edge of ø in the last T
another T
This is useful when inserting four or more T
be inserted for each external device.
Pin Auto-Wait Mode: A specified number of wait states T
between the T
settings of the WC1 and WC0 bits if the :$,7 pin is low at the falling edge of ø in the last T
state. Even if the :$,7 pin is held low, T
of states.
This function enables the low-speed memory interface only by inputting the chip select signal to
the :$,7 pin.
Figure 6.13 shows an example of wait state insertion timing in pin wait mode.
The settings after a reset are: 3-state access, 3 program wait insertion, and :$,7 pin input
disabled.
Rev. 2.0, 08/02, page 130 of 788
2
state and T
W
Wait Control
state is inserted. If the :$,7 pin is held low, T
3
2
2
state when accessing the external address space always according to the settings of
state and T
state and T
W
). There are three ways of inserting wait states: Program wait insertion, pin
3
3
state when accessing the external address space always according to
state when accessing the external address space according to the
W
states can be inserted only up to the specified number
W
states, or when changing the number of T
W
can be inserted automatically between the
W
W
W
states are inserted until it goes high.
can be inserted automatically
can be inserted automatically
2
or T
W
W
states to
state,
2