r4f2426 Renesas Electronics Corporation., r4f2426 Datasheet - Page 327

• Manufacturer Part Number: r4f2426
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2400 Series
• Manufacturer: Renesas Electronics Corporation.

When the BREQ pin is driven high, the BACK pin is driven high at the prescribed timing and the
external bus released state is terminated.
If an external bus release request and external access occur simultaneously, the order of priority is
as follows:
If a refresh request and external bus release request occur simultaneously, the order of priority is
as follows:
6.12.2
Table 6.14 shows pin states in the external bus released state.
Table 6.14 Pin States in Bus Released State
Pins
A23 to A0
D15 to D0
CSn (n = 7 to 0)
UCAS, LCAS
AS/AH
RD
OE
HWR, LWR
DACKn (n = 1, 0)
EDACKn (n = 3, 2)
(High) External bus release > External access by internal bus master (Low)
(High) Refresh > External bus release (Low)
Pin States in External Bus Released State
Pin State
High impedance
High impedance
High impedance
High impedance
High impedance
High impedance
High impedance
High impedance
High
High
Rev. 1.00 Sep. 19, 2008 Page 299 of 1270
Section 6 Bus Controller (BSC)
REJ09B0466-0100