HD64F2357F20V Datasheet, PDF (399/1049 Pages) Renesas Technology Corp – Hardware Manual Renesas 16-Bit Single-chip Microcomputer H8S Family / H8S/2300 Series

10.3 Interface to Bus Master
10.3.1 16-Bit Registers
TCNT and TGR are 16-bit registers. As the data bus to the bus master is 16 bits wide, these registers can be read and
written to in 16-bit units.
These registers cannot be read or written to in 8-bit units; 16-bit access must always be used.
An example of 16-bit register access operation is shown in figure 10-2.
Internal data bus
H
Bus
master ^L
Bus interface
Module
data bus
TCNTH
TCNTL
Figure 10-2 16-Bit Register Access Operation [Bus Master ↔ TCNT (16 Bits)]
Rev.6.00 Oct.28.2004 page 369 of 1016
REJ09B0138-0600H