Which of these conditional jumps can be used in the 8051 microcontroller to jump if a...
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Which of these conditional jumps can be used in the 8051 microcontroller to jump if a specific bit is set to one? - A) JC (Jump if Carry) - B) JZ (Jump if Zero) - C) JB (Jump if Bit is Set) (Jump if Not Zero) ek G&G 8 ®@
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The 8051 instruction set includes specific bit-addressable jump instructions. The 'JB' mnemonic stands for 'Jump if Bit set', which evaluates a specific bit in the bit-addressable memory space and performs a relative jump if that bit is 1.
Step-by-step Derivation:
Step 1: Analyze the requirements of the question. The goal is to find a conditional jump that triggers when a 'specific bit' is set to one.
Step 2: Evaluate Option A (JC). JC is 'Jump if Carry'. While the Carry flag is a bit, JC specifically checks the Carry flag (C) in the Program Status Word (PSW), not an arbitrary specific bit in memory.
Step 3: Evaluate Option B (JZ). JZ is 'Jump if Zero'. This instruction checks if the Accumulator (A) is equal to 0. It operates on a byte (8 bits), not a single specific bit.
Step 4: Evaluate Option C (JB). The JB instruction syntax is 'JB bit, rel'. It checks the status of the specified bit (either in the bit-addressable area of internal RAM or the Special Function Registers). If the bit is 1, the program jumps to the relative address provided.
Step 5: Conclusion: JB is the only instruction among the choices designed to jump based on the state of a specific, user-defined bit.