MC812A4CPVE8 Freescale Semiconductor, MC812A4CPVE8 Datasheet - Page 163

• Manufacturer Part Number: MC812A4CPVE8
• Description: IC MCU 16BIT EEPROM 4K 112-LQFP
• Manufacturer: Freescale Semiconductor
• Series: HC12r

Specifications of MC812A4CPVE8

• Core Processor: CPU12
• Core Size: 16-Bit
• Speed: 8MHz
• Connectivity: SCI, SPI
• Peripherals: POR, WDT
• Number Of I /o: 83
• Program Memory Size: 4KB (4K x 8)
• Program Memory Type: EEPROM
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 8x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 112-LQFP
• Processor Series: HC812A
• Core: HC12
• Data Bus Width: 16 bit
• Data Ram Size: 1 KB
• Interface Type: SCI, SPI
• Maximum Clock Frequency: 8 MHz
• Number Of Programmable I/os: 91
• Number Of Timers: 8
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit, 8 Channel
• Controller Family/series: 68HC12
• No. Of I/o's: 91
• Eeprom Memory Size: 4KB
• Ram Memory Size: 1KB
• Cpu Speed: 8MHz
• No. Of Timers: 1
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

Figure 14-10
synchronization with the start bit time, it does set the noise flag.
Figure 14-11
sample after the reset is low but is not preceded by three high samples that would qualify as a falling edge.
Depending on the timing of the start bit search and on the data, the frame may be missed entirely or it
may set the framing error flag.
In
the noise flag but does not reset the RT clock. In start bits only, the RT8, RT9, and RT10 data samples
are ignored.
Freescale Semiconductor
Figure 14-12
RT CLOCK COUNT
RT CLOCK COUNT
RT CLOCK COUNT
RESET RT CLOCK
RESET RT CLOCK
RESET RT CLOCK
RT CLOCK
RT CLOCK
RT CLOCK
SAMPLES
SAMPLES
SAMPLES
RXD
RXD
RXD
shows the effect of noise early in the start bit time. Although this noise does not affect proper
shows a burst of noise near the beginning of the start bit that resets the RT clock. The
a noise burst makes the majority of data samples RT8, RT9, and RT10 high. This sets
1
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Figure 14-10. Start Bit Search Example 4
Figure 14-11. Start Bit Search Example 5
Figure 14-12. Start Bit Search Example 6
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MC68HC812A4 Data Sheet, Rev. 7
1
1
1
1
1
1
0
0
0
1
0
0
PERCEIVED AND ACTUAL START BIT
0
1
0
START BIT
START BIT
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0
0
1
NO START BIT FOUND
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1
0
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0
Functional Description
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0
LSB
LSB
LSB
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