mc9s08rd60fj Freescale Semiconductor, Inc, mc9s08rd60fj Datasheet - Page 118

• Manufacturer Part Number: mc9s08rd60fj
• Description: Hcs08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Parallel Input/Output
8.6.3 Port C Registers (PTCD, PTCPE, and PTCDD)
Port C pins used as general-purpose I/O pins are controlled by the port C data (PTCD), data direction
(PTCDD), and pullup enable (PTCPE) registers.
PTCDn — Port C Data Register Bit n (n = 0–7)
PTCPEn — Pullup Enable for Port C Bit n (n = 0–7)
PTCDDn — Data Direction for Port C Bit n (n = 0–7)
118
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.
For port C pins that are inputs, these read/write control bits determine whether internal pullup devices
are enabled. For port C pins that are configured as outputs, these bits are ignored and the internal pullup
devices are disabled.
These read/write bits control the direction of port C pins and what is read for PTCD reads.
PTCD
PTCPE
PTCDD
1 = Internal pullup device enabled.
0 = Internal pullup device disabled.
1 = Output driver enabled for port C bit n and PTCD reads return the contents of PTCDn.
0 = Input (output driver disabled) and reads return the pin value.
Reset:
Reset:
Reset:
Read:
Read:
Read:
Write:
Write:
Write:
PTCDD7 PTCDD6 PTCDD5 PTCDD4 PTCDD3 PTCDD2 PTCDD1 PTCDD0
PTCPE7
PTCD7
Bit 7
0
0
0
Figure 8-8 Port C Registers
PTCPE6
PTCD6
6
0
0
0
MC9S08RC/RD/RE/RG
PTCPE5
PTCD5
5
0
0
0
PTCPE4
PTCD4
4
0
0
0
PTCPE3
PTCD3
3
0
0
0
PTCPE2
PTCD2
2
0
0
0
PTCPE1
PTCD1
Freescale Semiconductor
1
0
0
0
PTCPE0
PTCD0
Bit 0
0
0
0