Pin Description
The following table only includes the pins which are directly related to the MCU. The pin descriptions of the additional
peripheral functions are located at the corresponding section of the datasheet along with the relevant peripheral func-
tion functional description.
Pin Name
I/O
Options
Description
PA0~PA1
PA2/TMR
PA3~PA7
I/O
Pull-high
Wake-up
Bidirectional 8-bit input/output port. Each pin can be configured as a
wake-up input (both falling and rising edge) by a configuration option. Soft-
ware instructions determine if the pin is a CMOS output or Schmitt Trigger
input. Configuration options determine if the pins have pull-high resistors.
PA2 is shared with the external timer input pin TMR.
PB0/SCS
PB1~PB7
I/O
Pull-high or
Wake-up
CMOS/NMO
S
Bidirectional 8-bit input/output port. Each pin can be configured as a
wake-up input (both falling and rising edge) by a configuration option. Soft-
ware instructions determine if the pin is a CMOS output or Schmitt Trigger
input. Configuration options determine if the pins have pull-high resistors.
Also a configuration option determines if the PB0 is a CMOS output type or
NMOS output type. PB0 is shared with SCS of the SPI interface.
PC0~PC1
PC2/INT
PC3~PC4
PC5/SDI
PC6/SDO
PC7/SCK
I/O
Pull-high or
Wake-up
CMOS/NMO
S
Bidirectional 8-bit input/output port. Each pin can be configured as a
wake-up input (both falling and rising edge) by a configuration option. Soft-
ware instructions determine if the pin is a CMOS output or Schmitt Trigger
input. Configuration options determine if the pins have pull-high resistors.
Also a configuration option determines if the PC pins are CMOS output type
or NMOS output type. The INT is shared with PC2, PC5~PC7 are shared
with the SPI interface.
PD0~PD7
(HT82K75R only)
I/O
Pull-high or
Wake-up
Bidirectional 8-bit input/output port. Each nibble can be configured as
wake-up inputs (both falling and rising edge) by a configuration option. Soft-
ware instructions determine if the pin is a CMOS output or Schmitt Trigger
input. Configuration options determine if the pins have pull-high resistors.
PE0~PE7
(HT82K75R only)
I/O
Pull-high or
Wake-up
Bidirectional 8-bit input/output port. Each nibble can be configured as
wake-up inputs (both falling and rising edge) by a configuration option. Soft-
ware instructions determine if the pin is a CMOS output or Schmitt Trigger
input. Configuration options determine if the pins have pull-high resistors.
VSS
¾
¾
Negative power supply, ground
RES
I
¾
Schmitt Trigger reset input. Active low
VDD
¾
¾
Positive power supply
BAT_IN
I
¾
Battery input
LX
I
¾
DC/DC LX switch
VSSLX
I
¾
DC/DC ground
HT82M75REW/HT82K75REW
Rev. 1.00
3
June 11, 2010
electronic components distributor