H8SSLASH2218 datasheet(193/750 Pages) RENESAS

部件名	H8S/2218

功能描述	16-Bit Single-Chip Microcomputer H8S Family/H8S/2200 Series

PDF	750 Pages

Scroll/Zoom	100%

制造商	RENESAS [Renesas Technology Corp]

网页	http://www.renesas.com

标志

193 / 750 page

Section 6 Bus Controller

Rev.6.00 Jun. 03, 2008 Page 145 of 698

REJ09B0074-0600

6.6.4

Wait Control

When accessing external space, this LSI can extend the bus cycle by inserting one or more wait

states (Tw). There are two ways of inserting wait states: program wait insertion and pin wait

insertion using the

WAIT pin.

Program Wait Insertion: From 0 to 3 wait states can be inserted automatically between the T2

state and T3 state on an individual area basis in 3-state access space, according to the settings of

WCRH and WCRL.

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

WAIT pin in the H8S/2218 Group. When external space is accessed in this state, program wait

insertion is first carried out according to the settings in WCRH and WCRL. Then, if the

WAIT pin

is low at the falling edge of

φ in the last T

2 or TW state, a TW state is inserted. If the WAIT pin is

held low, TW states are inserted until it goes high.

H8S/2218 数据表(PDF) 193 Page - Renesas Technology Corp