Consider the following statements regarding 8051 instructions:
1. MOV instruction transfers data between registers/memory.
2. ADD instruction affects flags.
3. INC instruction affects carry flag.
Which of the above statements is/are correct?
Answer & step-by-step solution
The classic 8051 is an 8-bit Harvard-style microcontroller with separate code and data spaces. The standard core has 4 KB on-chip program ROM and 128 bytes internal RAM, supports external memory, multiple interrupts and configurable interrupt priority. Key relation: Reset SP=07H; classic internal RAM=128 bytes; standard ROM=4 KB.
Exam focus: Remember 07H for stack pointer reset. Common trap: 00H is not the reset value of the 8051 stack pointer.
Statement-wise Verification
- Statement 1 - Correct.
MOV instruction transfers data between registers/memory.
The classic 8051 is an 8-bit Harvard-style microcontroller with separate code and data spaces. - Statement 2 - Correct.
ADD instruction affects flags.
Remember 07H for stack pointer reset. - Statement 3 - Incorrect.
INC instruction affects carry flag.
8051 INC does not affect the carry flag
Core Concept
The classic 8051 is an 8-bit Harvard-style microcontroller with separate code and data spaces. The standard core has 4 KB on-chip program ROM and 128 bytes internal RAM, supports external memory, multiple interrupts and configurable interrupt priority. On reset the stack pointer is 07H, so the first PUSH stores at 08H.
Formula / Key Relationship
Reset SP=07H; classic internal RAM=128 bytes; standard ROM=4 KB.
Why the Other Options Are Wrong
Option A is incorrect because it omits correct statement(s) 2. Option B is incorrect because it includes incorrect statement(s) 3 and omits correct statement(s) 1. Option D is incorrect because it includes incorrect statement(s) 3.
Exam Shortcut / Approach
Remember 07H for stack pointer reset.
Common Mistake
00H is not the reset value of the 8051 stack pointer.
Quick Revision
MOV ADD and INC Flag Effects is linked with Instruction Set, 8051 Microcontroller and Microprocessors and Microcontrollers. Remember 07H for stack pointer reset.
8051 निर्देशों (instructions) के संबंध में निम्नलिखित कथनों पर विचार कीजिए:
1. MOV निर्देश रजिस्टरों/मेमोरी के बीच डेटा स्थानांतरित करता है।
2. ADD निर्देश फ्लैग्स को प्रभावित करता है।
3. INC निर्देश कैरी फ्लैग को प्रभावित करता है।
उपरोक्त में से कौन-सा/से कथन सही है/हैं?
उत्तर और चरणबद्ध हल
C — केवल 1 और 2। MOV डेटा स्थानांतरित करता है और ADD CY, AC, OV व P फ्लैग प्रभावित करता है। 8051 में INC कैरी फ्लैग (CY) को प्रभावित नहीं करता।
विस्तृत हल (मूल भाषा में)
Statement-wise Verification
- Statement 1 - Correct.
MOV instruction transfers data between registers/memory.
The classic 8051 is an 8-bit Harvard-style microcontroller with separate code and data spaces. - Statement 2 - Correct.
ADD instruction affects flags.
Remember 07H for stack pointer reset. - Statement 3 - Incorrect.
INC instruction affects carry flag.
8051 INC does not affect the carry flag
Core Concept
The classic 8051 is an 8-bit Harvard-style microcontroller with separate code and data spaces. The standard core has 4 KB on-chip program ROM and 128 bytes internal RAM, supports external memory, multiple interrupts and configurable interrupt priority. On reset the stack pointer is 07H, so the first PUSH stores at 08H.
Formula / Key Relationship
Reset SP=07H; classic internal RAM=128 bytes; standard ROM=4 KB.
Why the Other Options Are Wrong
Option A is incorrect because it omits correct statement(s) 2. Option B is incorrect because it includes incorrect statement(s) 3 and omits correct statement(s) 1. Option D is incorrect because it includes incorrect statement(s) 3.
Exam Shortcut / Approach
Remember 07H for stack pointer reset.
Common Mistake
00H is not the reset value of the 8051 stack pointer.
Quick Revision
MOV ADD and INC Flag Effects is linked with Instruction Set, 8051 Microcontroller and Microprocessors and Microcontrollers. Remember 07H for stack pointer reset.
8051 સૂચનાઓ (instructions) અંગે નીચેનાં વિધાનો ધ્યાનમાં લો:
1. MOV સૂચના રજિસ્ટરો/મેમરી વચ્ચે ડેટા ખસેડે છે.
2. ADD સૂચના ફ્લેગ્સને અસર કરે છે.
3. INC સૂચના કેરી ફ્લેગને અસર કરે છે.
ઉપરોક્તમાંથી કયું/કયાં વિધાન સાચું/સાચાં છે?
જવાબ અને પગલાવાર ઉકેલ
C — ફક્ત 1 અને 2. MOV ડેટા ખસેડે છે અને ADD CY, AC, OV અને P ફ્લેગને અસર કરે છે. 8051માં INC કેરી ફ્લેગ (CY)ને અસર કરતું નથી.
વિગતવાર ઉકેલ (મૂળ ભાષામાં)
Statement-wise Verification
- Statement 1 - Correct.
MOV instruction transfers data between registers/memory.
The classic 8051 is an 8-bit Harvard-style microcontroller with separate code and data spaces. - Statement 2 - Correct.
ADD instruction affects flags.
Remember 07H for stack pointer reset. - Statement 3 - Incorrect.
INC instruction affects carry flag.
8051 INC does not affect the carry flag
Core Concept
The classic 8051 is an 8-bit Harvard-style microcontroller with separate code and data spaces. The standard core has 4 KB on-chip program ROM and 128 bytes internal RAM, supports external memory, multiple interrupts and configurable interrupt priority. On reset the stack pointer is 07H, so the first PUSH stores at 08H.
Formula / Key Relationship
Reset SP=07H; classic internal RAM=128 bytes; standard ROM=4 KB.
Why the Other Options Are Wrong
Option A is incorrect because it omits correct statement(s) 2. Option B is incorrect because it includes incorrect statement(s) 3 and omits correct statement(s) 1. Option D is incorrect because it includes incorrect statement(s) 3.
Exam Shortcut / Approach
Remember 07H for stack pointer reset.
Common Mistake
00H is not the reset value of the 8051 stack pointer.
Quick Revision
MOV ADD and INC Flag Effects is linked with Instruction Set, 8051 Microcontroller and Microprocessors and Microcontrollers. Remember 07H for stack pointer reset.
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