SH7014 Datasheet, PDF (258/754 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

10. Multifunction Timer Pulse Unit (MTU)
10.3 Bus Master Interface
10.3.1 16-Bit Registers
The timer counters (TCNT) and general registers (TGR) are 16-bit registers. A 16-bit data bus to
the bus master enables 16-bit read/writes. 8-bit read/write is not possible. Always access in 16-bit
units. Figure 10.2 shows an example of 16-bit register access operation.
Internal data bus
Upper 8 bits
Module data bus
Bus master
Bus
interface
Lower 8 bits
TCNTH
TCNTL
Figure 10.2 16-Bit Register Access Operation (Bus Master ↔ TCNT (16 Bit))
10.3.2 8-Bit Registers
All registers other than the TCNT and general registers (TGR) are 8-bit registers. These are
connected to the CPU by a 16-bit data bus, so 16-bit read/writes and as 8-bit read/writes are both
possible (figures 10.3 to 10.5).
Internal data bus
Upper 8 bits
Module data bus
Bus master
Bus
interface
Lower 8 bits
TCR
Figure 10.3 8-Bit Register Access Operation (Bus Master ↔ TCR (Upper 8 Bits))
Rev.5.00 Sep. 27, 2007 Page 224 of 716
REJ09B0398-0500