MC68HC908AP64_07 FREESCALE [Freescale Semiconductor, Inc], MC68HC908AP64_07 Datasheet - Page 265

• Manufacturer Part Number: MC68HC908AP64_07
• Description: Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

16.2.3 Port-A LED Control Register (LEDA)
The port-A LED control register (LEDA) controls the direct LED drive capability on PTA7–PTA0 pins. Each
bit is individually configurable and requires that the data direction register, DDRA, bit be configured as an
output.
LEDA[7:0] — Port A LED Drive Enable Bits
16.3 Port B
Port B is an 8-bit special-function port that shares two of its pins with the multi-master IIC (MMIIC) module,
two of its pins with SCI module, and four of its pins with two timer interface (TIM1 and TIM2) modules.
16.3.1 Port B Data Register (PTB)
The port B data register contains a data latch for each of the eight port B pins.
PTB[7:0] — Port B Data Bits
Freescale Semiconductor
These read/write bits are software programmable to enable the direct LED drive on an output port pin.
These read/write bits are software-programmable. Data direction of each port B pin is under the control
of the corresponding bit in data direction register B. Reset has no effect on port B data.
1 = Corresponding port A pin is configured for direct LED drive,
0 = Corresponding port A pin is configured for standard drive
Alternative Function:
with 15mA current sinking capability
Address:
PTB3–PTB0 are open-drain pins when configured as outputs regardless
whether the pins are used as general purpose I/O pins, MMIIC pins, or SCI
pins. Therefore, when configured as general purpose output pins, MMIIC
pins, or SCI pins (the TxD pin), pullup resistors must be connected to these
pins.
Reset:
Read:
Write:
Address:
Reset:
Read:
Write:
LEDA7
$000C
Bit 7
0
Figure 16-5. Port A LED Control Register (LEDA)
T2CH1
$0001
PTB7
Bit 7
Figure 16-6. Port B Data Register (PTB)
LEDA6
6
0
MC68HC908AP Family Data Sheet, Rev. 4
T2CH0
PTB6
6
LEDA5
5
0
T1CH1
PTB5
5
NOTE
LEDA4
4
0
T1CH0
Unaffected by reset
PTB4
4
LEDA3
3
0
PTB3
RxD
3
LEDA2
2
0
PTB2
TxD
2
LEDA1
1
0
PTB1
SCL
1
LEDA0
Bit 0
0
PTB0
Bit 0
SDA
Port B
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