mc68hc08qa24 Freescale Semiconductor, Inc, mc68hc08qa24 Datasheet - Page 198

• Manufacturer Part Number: mc68hc08qa24
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Input/Output (I/O) Ports
16.6 Port D
16.6.1 Port D Data Register
Technical Data
196
NOTE:
Functions:
Address:
Alternate
Port D is a 6-bit, special function I/O port that shares some of its pins with
the analog-to-digital converter (ADC).
The port D data register contains a data latch for the seven port D pins.
PTD[5:0] — Port D Data Bits
ATD[11:8] — ADC Channel Status Bits
Data direction register D (DDRD) does not affect the data direction of
port D pins that are being used by the ADC. However, the DDRD bits
Reset:
Read:
Write:
PTD[5:0] are read/write, software programmable bits. Data direction
of PTD[5:0] pins are under the control of the corresponding bit in data
direction register D.
PTD3/ATD11–PTD0/ATD8 are four of the 12 analog-to-digital
converter channels. The ADC channel select bits, CH[4:0], determine
whether the PTD3/ATD11–PTD0/ATD8 pins are ADC channels or
general-purpose I/O pins. If an ADC channel is selected and a read of
this corresponding bit in the port B data register occurs, the data will
be 0 if the data direction for this bit is programmed as an input.
Otherwise, the data will reflect the value in the data latch. (See
Section 19. Analog-to-Digital Converter
$0003
Bit 7
R
R
0
Figure 16-11. Port D Data Register (PTD)
Input/Output (I/O) Ports
= Reserved
R
6
0
PTD5
5
Unaffected by reset
PTD4
4
ATD11
PTD3
3
(ADC).)
ATD10
PTD2
Freescale Semiconductor
2
MC68HC08QA24
PTD1
ATD9
1
PTD0
ATD8
Bit 0