MC68HC11E0CFNE3 Freescale Semiconductor, MC68HC11E0CFNE3 Datasheet - Page 25

• Manufacturer Part Number: MC68HC11E0CFNE3
• Description: IC MCU 8BIT 3MHZ 52-PLCC
• Manufacturer: Freescale Semiconductor
• Series: HC11r

Specifications of MC68HC11E0CFNE3

• Core Processor: HC11
• Core Size: 8-Bit
• Speed: 3MHz
• Connectivity: SCI, SPI
• Peripherals: POR, WDT
• Number Of I /o: 38
• Program Memory Type: ROMless
• Ram Size: 512 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: 52-PLCC
• Controller Family/series: 68HC11
• No. Of I/o's: 38
• Ram Memory Size: 512Byte
• Cpu Speed: 3MHz
• No. Of Timers: 1
• Embedded Interface Type: SCI, SPI
• Digital Ic Case Style: LCC
• Rohs Compliant: Yes
• Processor Series: HC11E
• Core: HC11
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: SCI, SPI
• Maximum Clock Frequency: 3 MHz
• Number Of Programmable I/os: 38
• 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
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -
• Lead Free Status / Rohs Status: Details

3.1.6.2 Overflow (V)
3.1.6.3 Zero (Z)
3.1.6.4 Negative (N)
3.1.6.5 Interrupt Mask (I)
3.1.6.6 Half Carry (H)
3.1.6.7 X Interrupt Mask (X)
TECHNICAL DATA
tions. Shift and rotate instructions operate with and through the carry bit to facilitate
multiple-word shift operations.
The overflow bit is set if an operation causes an arithmetic overflow. Otherwise, the V
bit is cleared.
The Z bit is set if the result of an arithmetic, logic, or data manipulation operation is
zero. Otherwise, the Z bit is cleared. Compare instructions do an internal implied sub-
traction and the condition codes, including Z, reflect the results of that subtraction. A
few operations (INX, DEX, INY, and DEY) affect the Z bit and no other condition flags.
For these operations, only = and - conditions can be determined.
The N bit is set if the result of an arithmetic, logic, or data manipulation operation is
negative (MSB = 1). Otherwise, the N bit is cleared. A result is said to be negative if its
most significant bit (MSB) is a one. A quick way to test whether the contents of a mem-
ory location has the MSB set is to load it into an accumulator and then check the status
of the N bit.
The interrupt request (IRQ) mask (I bit) is a global mask that disables all maskable in-
terrupt sources. While the I bit is set, interrupts can become pending, but the operation
of the CPU continues uninterrupted until the I bit is cleared. After any reset, the I bit is
set by default and can only be cleared by a software instruction. When an interrupt is
recognized, the I bit is set after the registers are stacked, but before the interrupt vector
is fetched. After the interrupt has been serviced, a return from interrupt instruction is
normally executed, restoring the registers to the values that were present before the
interrupt occurred. Normally, the I bit is zero after a return from interrupt is executed.
Although the I bit can be cleared within an interrupt service routine, “nesting” interrupts
in this way should only be done when there is a clear understanding of latency and of
the arbitration mechanism. Refer to SECTION 5 RESETS AND INTERRUPTS.
The H bit is set when a carry occurs between bits 3 and 4 of the arithmetic logic unit
during an ADD, ABA, or ADC instruction. Otherwise, the H bit is cleared. Half carry is
used during BCD operations.
The XIRQ mask (X) bit disables interrupts from the pin. After any reset, X is set by de-
fault and must be cleared by a software instruction. When an interrupt is recognized,
the X and I bits are set after the registers are stacked, but before the interrupt vector
is fetched. After the interrupt has been serviced, an RTI instruction is normally execut-
ed, causing the registers to be restored to the values that were present before the in-
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