MC68HC08LT8 Datasheet, PDF (100/156 Pages) Freescale Semiconductor, Inc – Microcontrollers

Input/Output (I/O) Ports
Table 9-3. Port B Pin Functions
DDRB Bit PTB Bit I/O Pin Mode
0
X⁽¹⁾
Input, Hi-Z⁽²⁾
1
X
Output
Accesses to DDRB
Read/Write
DDRB[7:6, 3:0]
DDRB[7:6, 3:0]
1. X = don’t care.
2. Hi-Z = high impedance.
3. Writing affects data register, but does not affect the input.
Accesses to PTB
Read
Write
Pin
PTB[7:6, 3:0]⁽³⁾
PTB[7:6, 3:0] PTB[7:6, 3:0]
9.3.3 Port B High Current Drive Control Register (HDB)
The port-B high current drive control register (HDB) controls the high current drive capability on PTB[3:2].
Each bit is individually configurable and requires that the data direction register, DDRB, bit be configured
as an output.
Address: $000C
Bit 7
6
5
4
3
2
1
Bit 0
Read:
0
0
0
0
0
0
HDB3
HDB2
Write:
Reset:
0
0
0
0
0
0
0
0
Figure 9-8. Port B High Current Drive Control Register (HDB)
HDB[3:2] — Port B High Current Drive Enable Bits
These read/write bits are software programmable to enable the direct LED drive on an output port pin.
1 = Corresponding port B pin is configured to high current sink direct LED drive.
0 = Corresponding port B pin is configured to standard drive
9.4 Port C
Port C is an 8-bit special function port that shares five of its port pins with the liquid crystal display (LCD)
driver module.
NOTE
PTC4–PTC5 pins are not available on 44-pin package.
9.4.1 Port C Data Register (PTC)
The port C data register contains a data latch for each of the eight port C pins.
Address:
Read:
Write:
Reset:
Alternative Function:
$0002
Bit 7
6
5
4
3
2
PTC7
PTC6
PTC5
PTC4
PTC3
PTC2
Unaffected by reset
FP24
FP23
FP22
FP21
Figure 9-9. Port C Data Register (PTC)
1
PTC1
FP20
Bit 0
PTC0
FP19
MC68HC08LT8 Data Sheet, Rev. 1
100
Freescale Semiconductor