HD64570 Datasheet, PDF (66/469 Pages) Hitachi Semiconductor – Serial Communications Adaptor

Table 2.6 Bus Interface Lines (cont)
Pin Number
Symbol
AS
CP-84
5
FP-88
16
Input/
Output
Description
Input/ Address strobe: Indicates whether the address
output bus is active.
CPU modes 0,1
Master mode
Output line. The address bus
(A₀−A₂₃) is valid when this line
is driven active low.
Slave mode Input, but ignored by the SCA.
Reset mode Input.
System stop Input.
mode
CPU modes 2, 3
Master mode
Output line. The address bus
(A₁−A₂₃) is valid when this line
is driven active low.
Slave mode
Input line. The SCA regards
the address bits (A₁−A₇) as
valid | when this line is driven
active low.
Reset mode Input.
System stop Input.
mode
Rev. 0, 07/98, page 50 of 453