mcf51ac256a Freescale Semiconductor, Inc, mcf51ac256a Datasheet - Page 113

• Manufacturer Part Number: mcf51ac256a
• Description: Mcf51ac Flexis
• Manufacturer: Freescale Semiconductor, Inc

6.5.3
Port C is a 7-bit input/output port and also shares its pins with the IIC and SCI2 peripherals and the MCLK
output. On reset the pins will default to the input state and under the I/O control. Enabling any of the shared
peripherals will take priority control over the pins. See
Port C is controlled by the registers listed below.
6.5.3.1
Freescale Semiconductor
Reset:
PTBDSn
PTCDn
Field
•
•
•
•
•
•
•
Field
7–0
6–0
W
R
PTC0 shares its pin with SCL1.
PTC1 shares its pin with SDA1.
PTC2 shares its pin with MCLK.
PTC3 shares its pin with TxD2.
PTC4 shares its pin with SS2.
PTC5 shares its pin with RxD2.
PTC6 shares its pin with FTM2FLT.
Port C Registers
Output Drive Strength Selection for Port B Bits — Each of these control bits selects between low and high
output drive for the associated PTB pin. For port B pins that are configured as inputs, these bits have no effect.
0 Low output drive strength selected for port B bit n.
1 High output drive strength selected for port B bit n.
Port C Data Register Bits — For port C pins that are inputs, reads return the logic level on the pin. For port C
pins that are configured as outputs, reads return the last value written to this register.
Writes are latched into all bits of this register. For port C pins that are configured as outputs, the logic level is
driven out the corresponding MCU pin.
Reset forces PTCD to all 0s, but these 0s are not driven out the corresponding pins because reset also configures
all port pins as high-impedance inputs with pullups disabled.
Port C Data Register (PTCD)
0
0
7
MCF51AC256 ColdFire Integrated Microcontroller Reference Manual, Rev. 5
PTCD6
0
6
Table 6-10. PTBDS Register Field Descriptions
Table 6-11. PTCD Register Field Descriptions
Figure 6-12. Port C Data Register (PTCD)
PTCD5
0
5
PTCD4
0
4
Description
Description
Table 2-1
PTCD3
3
0
for details on pin function priorities.
PTCD2
0
2
Parallel Input/Output Control
PTCD1
0
1
PTCD0
0
0
6-9