HD6433044 Datasheet, PDF (144/867 Pages) Hitachi Semiconductor – Hitachi Single-Chip Microcomputer

16-Bit, Two-State-Access Areas: Figures 6-9 to 6-11 show the timing of bus control signals for a
16-bit, two-state-access area. In these areas, the upper address bus (D₁₅ to D₈) is used to access
even addresses and the lower address bus (D₇ to D₀) is used to access odd addresses. Wait states
cannot be inserted.
ø
Address bus
CS _n
AS
RD
Read
access
D₁₅ to D₈
D₇ to D ₀
HWR
Write
access
LWR
D₁₅ to D₈
D₇ to D ₀
Bus cycle
T₁
T₂
Even external address in area n
Valid
Invalid
High
Valid
Undetermined data
Note: n = 7 to 0
Figure 6-9 Bus Control Signal Timing for 16-Bit, Two-State-Access Area (1)
(Byte Access to Even Address)
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