Datasheet

Section 2 CPU
Rev. 8.00 Mar. 09, 2010 Page 56 of 658
REJ09B0042-0800
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. Figures 2.12 and 2.13 show the on-chip peripheral module access cycle.
Two-state access to on-chip peripheral modules
T
1
state
Bus cycle
T
2
state
φ or φ
SUB
Internal address bus
Internal read signal
Internal data bus
(read access)
Internal write signal
Read data
Address
Write data
Internal data bus
(write access)
Figure 2.12 On-Chip Peripheral Module Access Cycle (2-State Access)