MC68HC05JJ6 Datasheet, PDF (99/216 Pages) Freescale Semiconductor, Inc – General Release Specification Microcontrollers

Parallel Input/Output
7.5 Port C (MC68HC05JP6 Only)
Port C is an 8-bit, general-purpose bidirectional I/O port with individual
programmable pulldown devices. It is only available on the 28-pin
MC68HC05JP6 device.
Port C has these features:
• Independent high and low nibble programmable pulldown devices
• High-current sinking capability on all port C pins with a maximum
of 15 mA per pin or a total of 60 mA for all eight pins
• High-current sourcing capability on all port C pins with a maximum
of 5 mA per pin or a total of 30 mA for all eight pins
7.5.1 Port C Data Register
The port C data register contains a bit for each of the port C pins. When
a port C pin is programmed to be an output, the state of its data register
bit determines the state of the output pin. When a port C pin is
programmed to be an input, reading the port C data register returns the
logic state of the pin.
$0002 Bit 7
6
5
4
3
2
1
Bit 0
Read:
PC7
PC6
PC5
PC4
PC3
PC2
PC1
PC0
Write:
Reset:
Unaffected by Reset
Figure 7-13. Port C Data Register (PORTC)
PC7–PC0 — Port C Data Bits
These read/write bits are software programmable. Data direction of
each bit is under the control of the corresponding bit in the port C data
direction register (DDRC). Reset has no effect on port C data.
NOTE:
For 20-pin devices, port C pins are not available. However, port C logic
is present on the MCU. Therefore, port C must be enabled as an output
or pulldowns must be enabled. This is to prevent floating input pins.
MC68HC05JJ6/MC68HC05JP6 — Rev. 3.2
Freescale Semiconductor
Parallel Input/Output
General Release Specification
99