XC68HC705F32 Motorola, XC68HC705F32 Datasheet - Page 30

• Manufacturer Part Number: XC68HC705F32
• Description: MICROCONTROLLER
• Manufacturer: Motorola

2
2.4.5
These eight I/O lines comprise the 8-bit port C, and are shared with other functions to give added
flexibility. During reset, these lines are configured as inputs. Port pins PC0 and PC1 are shared
with the input timer capture TCAP3 and TCAP4. Pins PC2 and PC3 are connected to the SCI
system (RDI, TDO), if the SCI is enabled. The remaining four pins, PC7–PC4, are connected to
the SPI system (SS, SCK, MOSI, MISO), if the SPI is enabled. All eight lines have internal
programmable pull-ups. If the PUEN bit in the system options register is cleared, the pull-ups are
disabled after reset. Setting the PUEN bit enables all the pull-up resistors in port C.
2.4.6
The eight I/O lines of port D are configured as inputs during power-on or reset. As all port D output
are open-drain, an external pull-up resistor is needed when a pin is being used as an output.
These port lines, PD7–PD0, are shared with the A/D converter, and are connected to it when the
corresponding port D control register bit is set to 1.
2.4.7
The VRH pin is the positive reference voltage for the A/D converter.
2.4.8
AVDD is the positive supply voltage for the A/D converter.
2.4.9
AVSS is the negative supply voltage and the negative reference voltage for the A/D converter.
2.4.10
The pins PE7–PE0 comprise port E, providing eight I/O lines when the port E control bits are set
to 0. As these pins are open-drain, an external pull-up resistor is needed when a pin is being used
as an output. These pins also share functions. When the corresponding port E register control bit
is set to 1, pins PE3–PE0 are connected to the timer system (TCMP2, TCAP2, TCMP1, TCAP1),
pin PE4 becomes REFRESH, and pins PE7–PE5 are connected to the PWM (PWM3–PWM1).
MOTOROLA
2-6
PC7/SS, PC6/SCK, PC5/MOSI, PC4/MISO, PC3/TDO,
PC2/RDI, PC1/TCAP4, PC0/TCAP3
PD7–PD0/AN7–AN0
VRH
AVDD
AVSS
PE7/PWM3, PE6/PWM2, PE5/PWM1, PE4/REFRESH,
PE3/TCMP2, PE2/TCAP2, PE1/TCMP1, PE0/TCAP1
MODES OF OPERATION AND PIN DESCRIPTIONS
MC68HC05F32
TPG