tmp86c847iug TOSHIBA Semiconductor CORPORATION, tmp86c847iug Datasheet - Page 60

• Manufacturer Part Number: tmp86c847iug
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

5.5 Port P4 (P47 to P40)
5. I/O Ports
5.5 Port P4 (P47 to P40)
(0004H)
(000FH)
control. Input/output mode is specified by the corresponding bit in the port P4 input/output control register (P4CR).
Port P4 is configured as an input if its corresponding P4CR bit is cleared to “0”, and as an output if its corresponding
P4CR bit is set to “1”.
“0”.
regardless of P4CR contents, therefore initial output data should be written into the output latch before setting P4CR.
P4DR
P4CR
R/W
Port P4 is an 8-bit input/output port which can be configured as an input or an output in one-bit unit under software
During reset, the P4CR is initialized to “0” and port P4 is input mode. The P4 output latches are also initialized to
When used as an input port, the corresponding bit of P4CR is cleared to “0”.
When used as an output port, the corresponding bit of P4CR is set to “1”. Data can be written into the output latch
Note: Ports set to the input mode read the pin states. Ports set to the output mode read the output latch. When input pin and out-
put pin exist in port P4 together, the contents of the output latch which is specified as an input mode may be rewritten by
executing the bit manipulation instructions.
P47
P4CR
7
7
Data input (P4DR)
P46
6
6
I/O control for port P4
(Specified for each bit)
P4CRi input
Data output
P4CRi
ST P
UTEN
P45
5
5
P44
4
4
utput latch
D
D
Figure 5-6 Port P4
Q
Q
P43
3
3
0: Input mode
1: Output mode
Page 52
P42
2
2
P41
1
1
P40
0
0
Note: i = 7
(Initial value: 0000 0000)
(Initial value: 0000 0000)
P4i
to
0
TMP86C847IUG
R/W