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3.5.5
Port 7 (P70 to P76)
Port 7 is a 7-bit general-purpose I/O port (P70 to P75 are used for output only).
Bits can be individually set as either inputs or outputs by control register P7CR and
function register P7FC.
In addition to functioning as a general-purpose I/O port, P70 to P73 pins can also
function as output pin of read/write strobe signals to connect with an external memory. P74
pin can also function as CLKOUT output pin when outputted internal clock. P76 pin can
also function as wait input.
After reset, P71 to P75 pins are set to output port mode, and P76 pin is set to input port
mode.
P70 pin set port 1 to pins of follow function by combination of AM1 and AM0 pins.
Reset
AM1
AM0
Function Setting after Reset
0
0
0
1
1
0
1
1
Function control
(on bit basis)
P7FC write
A
Output latch
P7 write
B
P7 read
,
,
RD
WRLL
CLKOUT, R/
W
Note: P73 is fixed to VCC.
Figure 3.5.9 Port 7 (P70 to P75)
92CM22-60
Don't use this setting
CPU control pin (
)
RD
CPU control pin (
)
RD
Don't use this setting
S
Selector
Output buffer
,
WRLU
TMP92CM22
Port 7
P70 (
)
RD
P71 (
)
WRLL
P72 (
)
WRLU
P73
P74 (CLKOUT)
P75 (R/
)
W
2007-02-16
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