HD64F2149 Datasheet, PDF (171/1035 Pages) Renesas Technology Corp – Hitachi 16-Bit Single-Chip Microcomputer

6.1.3 Pin Configuration
Table 6.1 summarizes the pins of the bus controller.
Table 6.1 Bus Controller Pins
Name
Address strobe
Symbol
AS
I/O
Output
I/O select
Read
IOS
Output
RD
Output
High write
HWR
Output
Low write
LWR
Output
Wait
WAIT
Input
Function
Strobe signal indicating that address output on
address bus is enabled (when IOSE bit is 0)
I/O select signal (when IOSE bit is 1)
Strobe signal indicating that external space is
being read
Strobe signal indicating that external space is
being written to, and that the upper data bus
(D15 to D8) is enabled
Strobe signal indicating that external space is
being written to, and that the lower data bus
(D7 to D0) is enabled
Wait request signal when external 3-state
access space is accessed
6.1.4 Register Configuration
Table 6.2 summarizes the registers of the bus controller.
Table 6.2 Bus Controller Registers
Name
Abbreviation
R/W
Bus control register
BCR
R/W
Wait state control register
WSCR
R/W
Note: * Lower 16 bits of the address.
Initial Value
H'D7
H'33
Address*
H'FFC6
H'FFC7
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