8085 microprocessor: “The temporary register in 8085 is a 16-bit register.” Evaluate the statement.

Introduction / Context:
Internal registers of the Intel 8085 include 8-bit general-purpose registers (B, C, D, E, H, L, A), a 16-bit program counter and stack pointer, and some internal temporary registers. Distinguishing their widths is important for assembly and micro-architecture understanding.

Given Data / Assumptions:

• 8085 has 8-bit data bus and 16-bit address bus.
• General-purpose registers are 8-bit, pairable to form 16-bit operands (e.g., HL, BC, DE).
• Internal temporary registers (often denoted W and Z) are 8-bit each but can be used as a 16-bit pair.

Concept / Approach:

The phrase “the temporary register is 16-bit” suggests a single 16-bit register. In 8085, the internal temporary storage commonly referenced consists of two 8-bit registers (W and Z) used together as a 16-bit pair when needed; individually they remain 8-bit. Therefore, calling “the” temporary register 16-bit is inaccurate.

Step-by-Step Solution:

Verification / Alternative check:

8085 microarchitecture documentation lists W and Z as 8-bit. The 16-bit entities are PC and SP, plus register pairs (BC, DE, HL) formed by two 8-bit registers.

Why Other Options Are Wrong:

• True: Overstates; not a single 16-bit temp register.
• True only for CALL/RET: Even then, it is a pair of 8-bit temps acting together.
• True when paired with accumulator: Accumulator pairing is not how a temp 16-bit register is formed.

Common Pitfalls:

Conflating register pairs with single registers; assuming address width (16-bit) implies internal temporary register width.

Final Answer:

False