Datasheet

Table Of Contents
Section 6 Bus Controller
REJ09B0140-0900 Rev. 9.00 Page 139 of 846
Sep 16, 2010
H8S/2215 Group
Figure 6.19 shows an example of wait state insertion timing.
By program
wait
T
1
Address bus
φ
AS
RD
Data bus
Read data
Read
HWR, LWR
Write data
Write
Note: indicates the timing of WAIT pin sampling.
WAIT
Data bus
T
2
T
w
T
w
T
w
T
3
By WAIT pin
Figure 6.19 Example of Wait State Insertion Timing
6.7 urst ROM Interface
With this LSI, external space area 0 can be designated as burst ROM space, and burst ROM
interfacing can be performed. The burst ROM space interface enables 16-bit configuration ROM
with burst access capability to be accessed at high speed.
Area 0 can be designated as burst ROM space by means of the BRSTRM bit in BCRH.
Consecutive burst accesses of a maximum of 4 words or 8 words can be performed for CPU
instruction fetches only. One or two states can be selected for burst access.