p2125vps20 Renesas Electronics Corporation., p2125vps20 Datasheet - Page 153

• Manufacturer Part Number: p2125vps20
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2100 Series
• Manufacturer: Renesas Electronics Corporation.

6.5.2
Table 6.4 shows the data buses used and valid strobes for each access space.
In a read, the RD signal is valid for both the upper and lower halves of the data bus. In a write, the
HWR signal is valid for the upper half of the data bus, and the LWR signal for the lower half. This
LSI has only the upper data bus and only the RD and HWR signals are enabled. The pin for HWR
signal in this LSI is WR.
Table 6.4
Notes: Undefined: Undefined data is output.
Area
8-bit
access space
16-bit
access space
(not available
in this LSI)
Invalid: Input state with the input value ignored.
Ports or others: Used as ports or I/O pins for on-chip peripheral modules, and are not used
as the data bus.
1. The pins in this LSI are D7 to D0.
2. The pin in this LSI is WR.
3. No pins are available in this LSI.
Valid Strobes
Data Buses Used and Valid Strobes
Access
Size
Byte
Byte
Word
Read/
Write
Read
Write
Read
Write
Read
Write
Address
—
—
Even
Odd
Even
Odd
—
—
Valid
Strobe
RD
HWR*
RD
HWR
LWR
RD
HWR, LWR
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Rev. 1.00 Sep. 21, 2006 Page 115 of 658
Upper Data Bus
(D15 to D8)*
Valid
Valid
Invalid
Valid
Undefined
Valid
Valid
Section 6 Bus Controller (BSC)
1
Lower Data Bus
(D7 to D0)*
Ports or others
Ports or others
Invalid
Valid
Undefined
Valid
Valid
Valid
REJ09B0310-0100
3