MC9S08QG84CDNER Freescale Semiconductor, MC9S08QG84CDNER Datasheet - Page 79

• Manufacturer Part Number: MC9S08QG84CDNER
• Description: IC MCU 8BIT B54 RATING 8-SOIC
• Manufacturer: Freescale Semiconductor
• Series: HCS08r

Specifications of MC9S08QG84CDNER

• Core Processor: HCS08
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SCI, SPI
• Peripherals: LVD, POR, PWM, WDT
• Number Of I /o: 4
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 3.6 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 8-SOIC (3.9mm Width)
• For Use With: DEMO9S08QG8E - BOARD DEMO FOR MC9S08QG8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Chapter 6
Parallel Input/Output Control
This section explains software controls related to parallel input/output (I/O) and pin control. The
MC9S08QG8 has two parallel I/O ports which include a total of 12 I/O pins, one output-only pin and one
input-only pin. See
assignments and external hardware considerations of these pins. Not all pins are available on all devices
of the MC9S08QG8/4 Family; see
device.
All of these I/O pins are shared with on-chip peripheral functions as shown in
modules have priority over the I/Os so that when a peripheral is enabled, the I/O functions associated with
the shared pins are disabled. After reset, the shared peripheral functions are disabled so that the pins are
controlled by the I/O. All of the I/Os are configured as inputs (PTxDDn = 0) with pullup devices disabled
(PTxPEn = 0), except for output-only pin PTA4 which defaults to the BKGD/MS pin.
6.1
Reading and writing of parallel I/Os is performed through the port data registers. The direction, either input
or output, is controlled through the port data direction registers. The parallel I/O port function for an
individual pin is illustrated in the block diagram shown in
Freescale Semiconductor
Port Data and Data Direction
Not all general-purpose I/O pins are available on all packages. To avoid
extra current drain from floating input pins, the user reset initialization
routine in the application program must either enable on-chip pullup devices
or change the direction of unconnected pins to outputs so the pins do not
float.
Section Chapter 2, “External Signal
MC9S08QG8 and MC9S08QG4 Data Sheet, Rev. 5
Table 1-1
for the number of general-purpose pins available on your
NOTE
Description,” for more information about pin
Figure
6-1.
Table
2-2. The peripheral
77