mc68hc908lv8 Freescale Semiconductor, Inc, mc68hc908lv8 Datasheet - Page 136

• Manufacturer Part Number: mc68hc908lv8
• Description: M68hc08 Microcontrollers 8-bit Microcontroller With Integrated Lcd Driver
• Manufacturer: Freescale Semiconductor, Inc

Input/Output (I/O) Ports
10.2 Port A
Port A is an 8-bit special function port that shares four of its port pins with the analog-to-digital converter
(ADC) module and four of its port pins with the keyboard interrupt module (KBI).
10.2.1 Port A Data Register (PTA)
The port A data register contains a data latch for each of the eight port A pins.
PTA[7:0] — Port A Data Bits
KBI[3:0] — Keyboard Interrupt Channels 3 to 0
ADC[3:0] — ADC channels 0 to 3
136
These read/write bits are software programmable. Data direction of each port A pin is under the control
of the corresponding bit in data direction register A. Reset has no effect on port A data.
KBI[3:0] are pins used for the keyboard interrupt input. The corresponding input, KBI[3:0], can be
enabled in the keyboard interrupt enable register, KBIER. Port pins used as KBI input will override any
control from the port I/O logic. See
ADC[3:0] are pins used for the input channels to the analog-to-digital converter module. The channel
select bits, ADCH[4:0], in the ADC status and control register define which port pin will be used as an
ADC input and overrides any control from the port I/O logic. See
Converter
Port
E
Alternative Function:
(ADC).
Bit
0
1
2
3
4
5
6
7
Address:
Table 10-1. Port Control Register Bits Summary (Sheet 2 of 2)
Reset:
Read:
Write:
DDRE0
DDRE1
DDRE2
DDRE3
DDRE4
DDRE5
DDRE6
DDRE7
DDR
$0000
ADC3
PTA7
Bit 7
Figure 10-2. Port A Data Register (PTA)
ADC2
PTA6
MC68HC908LV8 Data Sheet, Rev. 2
Module
Section 20. Keyboard Interrupt Module
6
LCD
PTA5
ADC1
5
CONFIG2 ($001D)
Module Control
LCDCR ($0051)
Register
Unaffected by Reset
ADC0
PTA4
4
PTA3
KBI3
3
Section 16. Analog-to-Digital
Control Bit
LCDE
PTA2
PEE
KBI2
2
(KBI).
PTA1
KBI1
1
Freescale Semiconductor
PTE7/FP10
PTE0/FP3
PTE1/FP4
PTE2/FP5
PTE3/FP6
PTE4/FP7
PTE5/FP8
PTE6/FP9
PTA0
KBI0
Bit 0
Pin