HD6433640 HITACHI [Hitachi Semiconductor], HD6433640 Datasheet - Page 55

• Manufacturer Part Number: HD6433640
• Description: H8/3644 Series Hardware Manual
• Manufacturer: HITACHI [Hitachi Semiconductor]

2.6.2
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 the operation timing in
the case of two-state access to an on-chip peripheral module.
ø or ø
Internal address bus
Internal read signal
Internal data bus
(read access)
Internal write signal
Internal data bus
(write access)
Access to On-Chip Peripheral Modules
Figure 2.12 On-Chip Peripheral Module Access Cycle (2-State Access)
SUB
T
1
state
Bus cycle
Address
Write data
Read data
T
2
state
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