MC68376BGMAB20 Freescale Semiconductor, MC68376BGMAB20 Datasheet - Page 191

• Manufacturer Part Number: MC68376BGMAB20
• Description: IC MCU 32BIT 8K ROM 160-QFP
• Manufacturer: Freescale Semiconductor
• Series: M683xxr

Specifications of MC68376BGMAB20

• Core Processor: CPU32
• Core Size: 32-Bit
• Speed: 20MHz
• Connectivity: CAN, EBI/EMI, SCI, SPI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 18
• Program Memory Type: ROMless
• Ram Size: 7.5K x 8
• Voltage - Supply (vcc/vdd): 4.75 V ~ 5.25 V
• Data Converters: A/D 16x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 160-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -

8.8.1 Port Data Register
8.8.2 Port Data Direction Register
MC68336/376
USER’S MANUAL
There are two special cases to consider for digital I/O port operation. When the MUX
(externally multiplexed) bit is set in QACR0, the data direction register settings are ig-
nored for the bits corresponding to PQA[2:0], the three multiplexed address MA[2:0]
output pins. The MA[2:0] pins are forced to be digital outputs, regardless of the data
direction setting, and the multiplexed address outputs are driven. The data returned
during a port data register read is the value of the multiplexed address latches which
drive MA[2:0], regardless of the data direction setting.
Similarly, when an external trigger queue operating mode is selected, the data direc-
tion register setting for the corresponding pins, PQA3 and/or PQA4, is ignored. The
port pins are forced to be digital inputs for ETRIG1 and/or ETRIG2. The data read
during a port data register read is the actual value of the pin, regardless of the data
direction register setting.
QADC ports A and B are accessed through two 8-bit port data registers (PORTQA and
PORTQB). Port A pins are referred to as PQA[7:0] when used as an 8-bit input/output
port. Port A can also be used for analog inputs AN[59:52], external trigger inputs
ETRIG[2:1], and external multiplexer address outputs MA[2:0].
Port B pins are referred to as PQB[7:0] when used as an 8-bit input-only digital port.
Port B can also be used for non-multiplexed AN[51:48]/AN[3:0] and multiplexed ANz,
ANy, ANx, ANw analog inputs.
PORTQA and PORTQB are unaffected by reset. Refer to D.5.4 Port A/B Data Reg-
ister for register and bit descriptions.
The port data direction register (DDRQA) is associated with the port A digital I/O pins.
These bidirectional pins have somewhat higher leakage and capacitance specifica-
tions. Refer to APPENDIX A ELECTRICAL CHARACTERISTICS for more informa-
tion.
Any bit in this register set to one configures the corresponding pin as an output. Any
bit in this register cleared to zero configures the corresponding pin as an input. Soft-
ware is responsible for ensuring that DDRQA bits are not set to one on pins used for
analog inputs. When a DDRQA bit is set to one and the pin is selected for analog
conversion, the voltage sampled is that of the output digital driver as influenced by the
load.
Since port B is input-only, a data direction register is not needed. Read operations on
the reserved bits in DDRQA return zeros, and writes have no effect. Refer to D.5.5
Port Data Direction Register for register and bit descriptions.
Caution should be exercised when mixing digital and analog inputs.
This should be minimized as much as possible. Input pin rise and fall
times should be as large as possible to minimize AC coupling effects.
QUEUED ANALOG-TO-DIGITAL CONVERTER MODULE
NOTE
MOTOROLA
8-9