The 8-Bit Computer by Ben Eater.

This code is an attempt to simulate Ben Eater's 8-bit computer.

Differences from the hardware

• UO micro-instruction
• I added a MDR between the RAM and the bus.

CPU PC 0 Bus 0 Acc 0 MAR 0 ALU 0 MDR 0 B 0 IR 0 NOP Simulation State STOPPED

uCPU uPC 0 uIR NO OP Status ZERO: 0 CARRY: 0 HALT: 0 I/O Output: 0

Memory Address Data 0 1 2 3 4 5 6 7 8 9 A B C D E F

Op Codes Value MNEMONIC Ben Dan 0 NOP nop 1 LDA load 2 ADD add 3 SUB subtract 4 STA store 5 LDI loadI 6 JMP jump 7 JC jumpC 8 JZ jumpZ 9     A     B     C     D     E OUT output F HLT halt

μCode μCode RTN AI ACC ← BUS AO BUS ← ACC BI B ← BUS CE PC ← PC + 1 CI PC ← BUS CO BUS ← PC EO BUS ← ALU II IR ← BUS IO BUS ← IR<3..0> J PC ← BUS MI MAR ← BUS RI MDR ← BUS RO BUS ← MDR SU ALU_OP = - UO μClock ← 0 HLT HALT ? If the specified flag is high raise dest ? ? Carry J, if carry is high, raise J

Program:

Control:

Clock Speed (cycle length in ms) : (Smaller is faster!)