274
5.15
Port F
5.15.1
Overview
Port F is an 8-bit I/O port. Port F pins also function as interrupt input pins (
IRQ14
and
IRQ15
),
bus control signal input/output pins (
AS
,
RD
,
HWR
,
LWR
,
LCAS
,
UCAS
, and
WAIT
), and the
system clock (ø) output pin. The
AS
and
LWR
output pins can be switched by making a setting in
PFCR2.
Figure 5.14 shows the port F pin configuration.
PF7 / ø
PF6 /
AS
PF5 /
RD
PF4 /
HWR
PF3 /
LWR
PF2 /
LCAS
/
IRQ15
PF1 /
UCAS
/
IRQ14
PF0 /
WAIT
Port F
Port F pins
PF7 (input) / ø (output)
PF6 (I/O) /
AS
(output)
RD
(output)
HWR
(output)
PF3 (I/O) /
LWR
(output)
PF2 (I/O) /
LCAS
(output) /
IRQ15
(input)
PF1 (I/O) /
UCAS
(output) /
IRQ14
(input)
PF0 (I/O) /
WAIT
(input)
Pin functions in modes 1, 2, 4, 5, and 6
Pin functions in mode 7
PF7 (input) / ø (output)
PF6 (I/O) /
AS
(output)
PF5 (I/O) /
RD
(output)
PF4 (I/O) /
HWR
(output)
PF3 (I/O) /
LWR
(output)
PF2 (I/O) /
LCAS
(output) /
IRQ15
(input)
PF1 (I/O) /
UCAS
(output) /
IRQ14
(input)
PF0 (I/O) /
WAIT
(input)
Figure 5.14 Port F Pin Functions
Summary of Contents for H8S/2670
Page 5: ......
Page 9: ......
Page 199: ...182 ...
Page 361: ...344 ...
Page 393: ...376 ...
Page 647: ...630 ...