MC9S08QG84CDNE Freescale Semiconductor, MC9S08QG84CDNE Datasheet - Page 181

• Manufacturer Part Number: MC9S08QG84CDNE
• Description: IC MCU 8BIT B54 RATING 8-SOIC
• Manufacturer: Freescale Semiconductor
• Series: HCS08r

Specifications of MC9S08QG84CDNE

• 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)
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: I2C, SCI, SPI
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 12
• Number Of Timers: 1
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 10 bit, 8 Channel
• For Use With: DEMO9S08QG8E - BOARD DEMO FOR MC9S08QG8
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

KBISC provided all enabled keyboard inputs are at their deasserted levels. KBF will remain set if any
enabled KBI pin is asserted while attempting to clear by writing a 1 to KBACK.
12.4.3
The KBI pins can be configured to use an internal pullup/pulldown resistor using the associated I/O port
pullup enable register. If an internal resistor is enabled, the KBIES register is used to select whether the
resistor is a pullup (KBEDGn = 0) or a pulldown (KBEDGn = 1).
12.4.4
When a keyboard interrupt pin is first enabled it is possible to get a false keyboard interrupt flag. To
prevent a false interrupt request during keyboard initialization, the user should do the following:
Freescale Semiconductor
1. Mask keyboard interrupts by clearing KBIE in KBISC.
2. Enable the KBI polarity by setting the appropriate KBEDGn bits in KBIES.
3. If using internal pullup/pulldown device, configure the associated pullup enable bits in PTxPE.
4. Enable the KBI pins by setting the appropriate KBIPEn bits in KBIPE.
5. Write to KBACK in KBISC to clear any false interrupts.
6. Set KBIE in KBISC to enable interrupts.
KBI Pullup/Pulldown Resistors
KBI Initialization
MC9S08QG8 and MC9S08QG4 Data Sheet, Rev. 5
Keyboard Interrupts (S08KBIV2)
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