8085 Microprocessor Sandbox · Microprocessor

8085 microprocessorInternal architecture · 40-pin DIP · colour-coded pin groups

Internal blocks

ALU + accumulatorArithmetic, logic and the working register

IR & decoderHolds the fetched opcode and decodes it

Timing & controlGenerates RD, WR, ALE, S0, S1, IO/M and the clock

Buffers & busesCarry the 16-bit address and 8-bit data to the pins

Interrupt controlTRAP, RST 5.5 / 6.5 / 7.5, INTR and INTA

Serial I/O controlSID input and SOD output

Pin groups

Power & clock

X1, X2, CLK OUT, VCC, VSS

Address / data bus

A8–A15, AD0–AD7, ALE

Control & status

S0, S1, IO/M, RD, WR, READY, HOLD, HLDA

Interrupts

TRAP, RST 7.5, RST 6.5, RST 5.5, INTR, INTA

Reset & serial I/O

RESET IN, RESET OUT, SID, SOD

Pins

40DIP package

Registers

6 GPRB C D E H L

Data bus

8-bitAD0–AD7

Address bus

16-bitA0–A15

Switch between the two views with the tabs above the diagram. On the architecture view, trace how the decoder feeds the internal 8-bit data bus and how the buffers drive the multiplexed AD0–AD7 lines. On the pin view, each signal is colour-coded by group — power, buses, control, interrupts and serial I/O.

8085 8-bit microprocessor

Every block works off the internal 8-bit data bus. The ALU and accumulator do the arithmetic, the register array (B C D E H L, plus temporary W and Z) holds the operands, the IR and decoder and the timing and control unit drive the fetch–decode–execute cycle, and the address and data buffers carry everything out to the 40 pins.