A program should be a sequence of 8, 16, or 32 hexadecimal characters. The first two characters represent the byte in memory location 0, and so on and etc.

The editor ignores whitespace and any characters on a line after a # character. So here's an example program you can submit (it's the 4-byte busy beaver described in the paper.)

      31 # Subtract 1 from the accumulator
      01 # NOP, also the literal value 1
      70 # Jump to the first instruction if the carry bit is set
      43 # Overwrite this instruction with the contents of the accumulator

8 byte instructions take the form of a 4-bit opcode and 4-bit operand

      0 - NOP     do nothing
      1 - LDA     a = M[operand]
      2 - ADD     a = a + M[operand]
      3 - SUB     a = a - M[operand]
      4 - STA     M[operand] = a
      5 - LDI     a = operand
      6 - JMP     pc = operand
      7 - JC      pc = operand if the carry flag is set
      8 - JZ      pc = operand if the zero flag is set
      9 - invalid
      A - invalid
      B - invalid
      C - invalid
      D - invalid
      E - OUT     display the contents of a
      F - HLT     halts the machine

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