MC68HC908JB8JDW Freescale Semiconductor, MC68HC908JB8JDW Datasheet - Page 203

• Manufacturer Part Number: MC68HC908JB8JDW
• Description: IC MCU 8K FLASH 3MHZ 20-SOIC
• Manufacturer: Freescale Semiconductor
• Series: HC08r

Specifications of MC68HC908JB8JDW

• Core Processor: HC08
• Core Size: 8-Bit
• Speed: 3MHz
• Connectivity: USB
• Peripherals: LVD, POR, PWM
• Number Of I /o: 13
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 20-SOIC (7.5mm Width)
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -
• Data Converters: -

12.3.2 Data Direction Register A
MC68HC908JB8•MC68HC08JB8•MC68HC08JT8 — Rev. 2.3
Freescale Semiconductor
NOTE:
* DDRA7 bit is reset by POR or LVI reset only.
Address:
Data direction register A determines whether each port A pin is an input
or an output. Writing a logic 1 to a DDRA bit enables the output buffer for
the corresponding port A pin; a logic 0 disables the output buffer.
DDRA[7:0] — Data Direction Register A Bits
Avoid glitches on port A pins by writing to the port A data register before
changing data direction register A bits from 0 to 1.
Figure 12-4
Reset:
Read:
Write:
These read/write bits control port A data direction. Reset clears
DDRA[7:0], configuring all port A pins as inputs.
1 = Corresponding port A pin configured as output
0 = Corresponding port A pin configured as input
DDRA7
READ DDRA ($0004)
WRITE DDRA ($0004)
WRITE PTA ($0000)
READ PTA ($0000)
$0004
Bit 7
0*
Figure 12-3. Data Direction Register A (DDRA)
shows the port A I/O logic.
Input/Output Ports (I/O)
DDRA6
6
0
Figure 12-4. Port A I/O Circuit
RESET
DDRA5
0
5
DDRA4
DDRAx
0
4
PTAx
DDRA3
0
3
DDRA2
0
2
Input/Output Ports (I/O)
DDRA1
1
0
Technical Data
DDRA0
Bit 0
Port A
0
PTAx
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