3069RF-ZTAT Datasheet, PDF (413/1003 Pages) Renesas Technology Corp – RENESAS 16-BIT SINGLE-CHIP MICROCOMPUTER

10.3 CPU Interface
10.3.1 8-Bit Registers
8TCNT, TCORA, TCORB, 8TCR, and 8TCSR are 8-bit registers. These registers are connected
to the CPU by an internal 16-bit data bus and can be read and written a word at a time or a byte at
a time.
Figures 10.2 and 10.3 show the operation in word read and write accesses to 8TCNT.
Figures 10.4 to 10.7 show the operation in byte read and write accesses to 8TCNT0 and 8TCNT1.
Internal data bus
H
C
PL
U
Bus
interface
H
L ^{Module data bus}
8TCNT0 8TCNT1
Figure 10.2 8TCNT Access Operation (CPU Writes to 8TCNT, Word)
Internal data bus
H
C
PL
U
Bus
interface
H
L ^{Module data bus}
8TCNT0 8TCNT1
Figure 10.3 8TCNT Access Operation (CPU Reads 8TCNT, Word)
Internal data bus
H
C
PL
U
Bus
interface
H
L ^{Module data bus}
8TCNTH0 8TCNTL1
Figure 10.4 8TCNT0 Access Operation (CPU Writes to 8TCNT0, Upper Byte)
Rev. 5.0, 09/04, page 391 of 978