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HT46R003B
Cost-Effective A/D 8-bit OTP MCU
HT46R003B
Cost-Effective A/D 8-bit OTP MCU
PBC Register
Bit
7
6
5
4
3
2
1
0
Name
—
—
PBC5
PBC�
PBC3
PBC�
PBC1
PBC0
R/W
—
—
R/W
R/W
R/W
R/W
R/W
R/W
POR
—
—
1
1
1
1
1
1
Bit 7~6
Unimplemented, read as "0"
Bit 5~0
PBC5~PBC0
: Port B bit 5~ bit 0 Input/Output control
0: Output
1: Input
Pin-shared Functions
The flexibility of the microcontroller range is greatly enhanced by the use of pins that have more
than one function. Limited numbers of pins can force serious design constraints on designers but by
supplying pins with multi-functions, many of these difficulties can be overcome. For some pins, the
chosen function of the multi-function I/O pins is set by application program control.
• External Interrupt Input
The external interrupt pin, INT, is pin-shared with an I/O pin. To use the pin as an external
interrupt input the correct bits in the INTC0 register must be programmed. The pin must also be
set as an input by setting the PAC6 bit in the Port Control Register. A pull-high resistor can also
be selected via the appropriate port pull-high resistor register. Note that even if the pin is set as an
external interrupt input the I/O function still remains.
• External Timer/Event Counter Input
The Timer/Event Counter pin TMR is pin-shared with I/O pins For this shared pin to be used
as Timer/Event Counter input, the Timer/Event Counter must be configured to be in the Event
Counter or Pulse Width Capture Mode. This is achieved by setting the appropriate bits in the
Timer/Event Counter Control Register. The pin must also be set as input by setting the appropriate
bit in the Port Control Register. Pull-high resistor options can also be selected using the port
pull-high resistor registers. Note that even if the pin is set as an external timer input the I/O
function still remains.
• PFD Output
The PFD function output is pin-shared with an I/O pin. The output function of this pin is chosen
using the CTRL0 register. Note that the corresponding bit of the port control register must be
set the pin as an output to enable the PFD output. If the port control register has set the pin as an
input, then the pin will function as a normal logic input with the usual pull-high selection, even if
the PFD function has been selected.
• PWM Output
For the device the PWM function is included. The PWM function whose outputs are pin-shared
with I/O pins. The PWM output functions are chosen using the CTRL0 register. Note that the
corresponding bit of the port control registers, for the output pin, must setup the pin as an output
to enable the PWM output. If the pins are setup as inputs, then the pin will function as a normal
logic input with the usual pull-high selections, even if the PWM registers have enabled the PWM
function.