h8s-2628 Renesas Electronics Corporation., h8s-2628 Datasheet - Page 135

• Manufacturer Part Number: h8s-2628
• Description: Renesas 16-bit Single-chip Microcomputer H8s Family/h8s/2600 Series
• Manufacturer: Renesas Electronics Corporation.

The H8S/2600 CPU is driven by a system clock, denoted by the symbol .
The bus controller controls a memory cycle and a bus cycle. Different methods are used to access
on-chip memory and on-chip support modules. The bus controller also has a bus arbitration
function, and controls the operation of the internal bus masters: the CPU and data transfer
controller (DTC).
7.1
The period from one rising edge of to the next is referred to as a “state”. The memory cycle or
bus cycle consists of one, two, three, or four states. Different methods are used to access on-chip
memory and on-chip support modules.
7.1.1
On-chip memory is accessed in one state. The data bus is 16 bits wide, permitting both byte and
word transfer instruction. Figure 7.1 shows the on-chip memory access cycle.
Basic Timing
On-Chip Memory Access Timing (ROM, RAM)
Internal address bus
Read
Write
Figure 7.1 On-Chip Memory Access Cycle
Internal read signal
Internal data bus
Internal write signal
Internal data bus
Section 7 Bus Controller
Bus cycle
Address
T
1
Rev. 3.00 Oct 04, 2005 page 95 of 598
Read data
Write data
Section 7 Bus Controller
REJ09B0155-0300