HD6412320 RENESAS [Renesas Technology Corp], HD6412320 Datasheet - Page 202

• Manufacturer Part Number: HD6412320
• Description: Renesas 16-Bit Single-Chip Microcomputer H8S Family H8S-2300 Series
• Manufacturer: RENESAS [Renesas Technology Corp]

Section 6 Bus Controller
6.4.3
Table 6.4 shows the data buses used and valid strobes for the access spaces.
In a read, the RD signal is valid without discrimination between 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.
Table 6.4
Area
8-bit access
space
16-bit access
space
Notes: Hi-Z: High impedance
Rev.6.00 Sep. 27, 2007 Page 172 of 1268
REJ09B0220-0600
Invalid: Input state; input value is ignored.
Valid Strobes
Data Buses Used and Valid Strobes
Access
Size
Word
Byte
Byte
Read/
Write
Read
Write
Read
Write
Read
Write
Address
Even
Odd
—
—
—
—
Even
Odd
Valid
Strobe
RD
HWR
RD
HWR
LWR
RD
HWR, LWR Valid
Upper Data Bus
(D
Valid
Hi-Z
Valid
Valid
Valid
Invalid
15
to D
8
)
Lower Data Bus
(D
Hi-Z
Valid
Valid
Valid
Invalid
Hi-Z
Invalid
Valid
7
to D
0
)