HT45R37V Holtek Semiconductor Inc., HT45R37V Datasheet - Page 3

• Manufacturer Part Number: HT45R37V
• Description: C/r-f Type 8-bit Otp Mcu
• Manufacturer: Holtek Semiconductor Inc.

Pin Description
Rev. 1.00
PA0/BZ/RC0
PA1/BZ/RC1
PA2/TMR0/RC2
PA3/PFD/RC3
PA4/TMR1/SCS/RC4
PA5/SCK/SCL/RC5
PA6/INT0/SDI/SDA/RC6
PA7/INT1/SDO/RC7
PB0/AN0
PB1/AN1
PB2/F1
PB3/STROBE
PB4/CLK
PB5/DATA
PC0/RES
PC1/OSC1
PC2/OSC2
PC3/OSC3
PC4/OSC4
Pin Name
SIM
I/O
I/O
I/O
I/O
I/O
I/O
I/O
3.Ext. RC OSC
Configuration
1.Int. RC OSC
2.Crystal OSC
PC0 or RES
RC0~RC7
RTC OSC
Option
BZ/BZ
PFD
Bidirectional 8-bit input/output port. Each individual bit on this port
can be configured as a wake-up input using the PAWU register.
Software instructions determine if the pin is a CMOS output or
Schmitt trigger input. A pull high resistor can be connected to each
pin using the PAPU register. Pins PA0, PA1, PA3, PA2, PA4, PA6
and PA7 are shared with BZ, BZ, PFD, TMR0, TMR1, INT0 and
INT1 respectively. PA7 is also pin-shared with the SPI bus data
output line, SDO. PA6 is also pin-shared with the SPI bus data line,
SDI and the I
SPI bus clock line, SCK, and the I
also pin-shared with the SPI bus select line, SCS. The C/R to F
converter inputs RC0~RC7 are shared with pins Pins PA0~PA7
respectively.
Bidirectional 2-bit input/output port. Software instructions deter-
mine if the pin is a CMOS output or Schmitt trigger input. A pull
high resistor can be connected to each pin using the PBPU regis-
ter. PB is pin-shared with the A/D input pins. The A/D inputs are se-
lected via software instructions. Once selected as an A/D input,
the I/O function and pull-high resistor selections are disabled auto-
matically.
Bidirectional 4-bit internal input/output port. Software instructions
determine if the pin is a CMOS output or Schmitt trigger input. A
pull high resistor can be connected to each pin using the PBPU
register.
PB2~PB5 are used to control the VFD driver interface by selected
as the I/O function. These pins should only be used as outputs and
as VFD interface pins and not as normal I/O pins.
Bidirectional line I/O. Software instructions determine if the pin is
an NMOS output or Schmitt Trigger input. A configuration option
determines if the pin is to be used as a RES pin or as an I/O pin.
This pin does not have an internal pull-high function.
Bidirectional 2-line I/O. Software instructions determine if the pins
are CMOS outputs or Schmitt Trigger inputs. A pull high resistor
can be connected to each pin using the PCPU register. Configura-
tion options determine if the pins are to be used as oscillator pins
or I/O pins. Configuration options also determine which oscillator
mode is selected. The three oscillator modes are:
1. Internal RC OSC: both pins configured as I/Os.
2. External crystal OSC: both pins configured as OSC1/OSC2.
3. External RC OSC+PC2: PC1 is configured as OSC1 pin, PC2
configured as an I/O.
If the internal RC OSC is selected, the frequency will be fixed at either
4MHz, 8MHz or 12MHz, dependent upon which configuration option
is chosen.
Bidirectional 2-line I/O. Software instructions determine if the pins
are CMOS outputs or Schmitt Trigger inputs. A pull high resistor
can be connected to each pin using the PCPU register. Configura-
tion options determine if the pins are to be used as oscillator pins
or I/O pins. If configuration options select oscillator pins, the pins
are connected to a 32768Hz crystal oscillator.
3
2
C Bus data line SDA. PA5 is also pin-shared with the
Description
2
C Bus clock line SCL. PA4 is
October 20, 2009
HT45R37V