H8SLASH3028F datasheet(179/923 Pages) RENESAS

部件名	H8/3028F

功能描述	Renesas 16-Bit Single-Chip Microcomputer H8 Family/H8/300H Series

PDF	923 Pages

Scroll/Zoom	100%

制造商	RENESAS [Renesas Technology Corp]

网页	http://www.renesas.com

标志

179 / 923 page

Rev. 2.00, 09/03, page 149 of 890

Pin Wait Insertion: Setting the WAITE bit in BCR to 1 enables wait insertion by means of the

WAIT pin. When external space is accessed in this state, a program wait is first inserted. If the

WAIT pin is low at the falling edge of φ in the last T2 or TW state, another TW state is inserted. If

the

WAIT pin is held low, T

W states are inserted until it goes high.

This is useful when inserting four or more TW states, or when changing the number of TW states

for different external devices.

The WAITE bit setting applies to all areas. Pin waits cannot be inserted in DRAM space.

Figure 6.17 shows an example of the timing for insertion of one program wait state in 3-state

space.

WAIT

Address bus

Data bus

Read access

Write access

Data bus

HWR, LWR

Note:

indicates the timing of

WAIT pin sampling.

Inserted

by program wait Inserted by

WAIT pin

Read data

Write data

Figure 6.17 Example of Wait State Insertion Timing

H8/3028F 数据表(PDF) 179 Page - Renesas Technology Corp