tmp88ch40mg TOSHIBA Semiconductor CORPORATION, tmp88ch40mg Datasheet - Page 47

• Manufacturer Part Number: tmp88ch40mg
• Description: 8 Bit Microcontroller
• Manufacturer: TOSHIBA Semiconductor CORPORATION

5.4 Port P6 (P63 to P60)
P6 port input/output registers
Control output (P6)
(01F8CH)
(00006H)
and output modes using the P6 port input/output control register (P6CR), P6 port output latch (P6DR), and ADC-
CRA<AINDS>. When reset, the P6CR Register and the P6DR output latch are initialized to 0 while ADC-
CRA<AINDS> is set to 1, so that P63 to P60 have their inputs fixed low (= 0). When using the P6 port as an input
port, set the corresponding bits for input mode (P6CR = 0, P6DR = 1). The reason why the output latch = 1 is
because it is necessary to prevent current from flowing into the shared data input circuit. When using the port as an
output port, set the P6CR Register's corresponding bits to 1. When using the port for analog input, set the corre-
sponding bits for analog input (P6CR = 0, P6DR = 0). Then set ADCCRA<AINDS> = 0, and AD conversion will
start.
AD conversion are selected using ADCCRA<SAIN>.
instructions on these ports during AD conversion. This is necessary to maintain the accuracy of AD conversion.
Also, do not apply rapidly changing signals to ports adjacent to analog input during AD conversion.
P6DR
P6CR
R/W
ata output (P6)
Port P6 is an 4-bit input/output port shared with AD converter analog input. This port is switched between input
The ports used for analog input must have their output latches set to 0 beforehand. The actual input channels for
Although the bits of P6 port not used for analog input can be used as input/output ports, do not execute output
If an input instruction is executed while the P6DR output latch is cleared to 0, data “0” is read in from said bits.
Note 1: The pins used for analog input cannot be set for output mode (P6CR = 1) because they become shorted with external
Note 2: When a read instruction is executed on bits of this port which are set for analog input mode, data "0" is read in.
Note 3: For DBOUT output, set the P6DR (P63) output latch to 1.
Note 4: *: Don’t care
Note 5: When using this port in input mode (including analog input), do not use bit manipulating or other read-modify-write instruc-
ata input (P6)
Analog input
P6CRi input
AIN S
P6CRi
signals.
tions. When a read instruction is executed on the bits of this port that are set for input, the contents of the pins are read in,
so that if a read-modify-write instruction is executed, their output latches may be rewritten, making the pins unable to
SAIN
P6CR
7
7
6
6
P6 port input/output control
(Specify bitwise)
Q
Q
5
5
4
4
Figure 5-5 Port P6
DBOUT
AIN3
P63
3
3
0
1
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Inputs fixed to
AIN2
AINDS = 1 (when not using AD)
P62
P6DR = “0”
2
2
0
Output mode
AIN1
P61
1
1
P6DR = “1”
Input mode
AIN0
P60
0
0
P6i
Note 1: i = 3
Note 2: SAIN selects A input channels.
(Initial value: **** 0000)
(Initial value: **** 0000)
mode (Note2)
Analog input
P6DR = “0”
AINDS = 0 (when using AD)
to
0
Output mode
TMP88CH40MG
P6DR = “1”
Input mode
R/W