H83627 Datasheet, PDF (54/381 Pages) Renesas Technology Corp – single-chip microcomputers

2.6.2 Access to On-Chip Peripheral Modules
On-chip peripheral modules are accessed in two states or three states. The data bus width is 8 bits,
so access is by byte size only. This means that for accessing word data, two instructions must be
used.
Two-state access to on-chip peripheral modules
Figure 2.12 shows operation timings for accessing on-chip peripheral modules in 2 states.
ø or ø_SUB
Bus cycle
T₁ state
T₂ state
Internal address bus
Address
Internal read signal
Internal data bus
(read access)
Read data
Internal write signal
Internal data bus
(write access)
Write data
Figure 2.12 On-Chip Peripheral Module Access Cycle (2-State Access)
Three-state access to on-chip peripheral modules
Figure 2.13 shows operation timings for accessing on-chip peripheral modules in 3 states.
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