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  • Instructions

    • 0x0

      • 0x00E0 Clear screen
      • 0x00EE Return from subroutine
      • 0x0NNN Call machine code routine at NNN

    • 0x1

      • 0x1NNN Goto NNN

    • 0x2

      • 0x2NNN Call subroutine at NNN

    • 0x3

      • 0x3XNN Skip the next instruction if value in Reg X is Equal to NN

    • 0x4

      • 0x4XNN Skip the next instruction if value in Reg X is Not Equal to NN

    • 0x5

      • 0x5XY0 Skip the next instruction if the values in Regs X and Y are Equal

    • 0x6

      • 0x6XNN Set the value of Reg X to number NN

    • 0x7

      • 0x7XNN Add NN to the value in Reg X (carry flag not altered)

    • 0x8

      • 0x8XY0 Set value of Reg X with the value of Reg Y
      • 0x8XY1 Set value of Reg X with the bitwise OR of the values in Regs X and Y [V(X) = V(X) | V(Y)]
      • 0x8XY2 Set value of Reg X with the bitwise AND of the values in Regs X and Y [V(X) = V(X) & V(Y)]
      • 0x8XY3 Set value of Reg X with the bitwise XOR of the values in Regs X and Y [V(X) = V(X) ^ V(Y)]
      • 0x8XY4 Set value of Reg X with the Addition of the values in Regs X and Y [V(X) = V(X) + V(Y)] Set VF to 1 on overflow, otherwise to 0
      • 0x8XY5 Set value of Reg X with the Subtraction of the values in Regs X and Y [V(X) = V(X) - V(Y)] Set VF to 0 if underflow, otherwise to 1
      • 0x8XY6 Right shift by one the value of Reg X and store the LSB of value (prior to shift) to VF
      • 0x8XY7 Set value of Reg X with the Subtraction of the values in Regs Y and X [V(X) = V(Y) - V(X)] Set VF to 0 if underflow, otherwise to 1
      • 0x8XYE Left shift by one the value of Reg X and store the MSB of value (prior to shift) to VF

    • 0x9

      • 0x9XY0 Skip next instruction if the values of Regs X and Y are Not Equal

    • 0xA

      • 0xANNN Set the Index Reg to the address/value NNN

    • 0xB

      • 0xBNNN Jump to address NNN plus V0

    • 0xC

      • 0xCXNN Set the value of Reg X to a random number between 0 and 255 (inclusive), and mask it with NN

    • 0xD

      • 0xDXYN Draw a sprite at coordinate [V(X), V(Y)] (values of Regs X, Y). The sprite has an 8 pixels width and an N pixels height.

    • 0xE

      • 0xEX9E Skip instruction if the key stored in Reg X is being pressed.
      • 0xEXA1 Skip instruction if the key stored in Reg X is NOT being pressed.

    • 0xF

      • 0xFX07 Set the value of Reg X to the Delay timer value.
      • 0xFX0A Set the value of Reg X to the value of the key pressed [blocking!].
      • 0xFX15 Set Delay timer to the value of Reg X
      • 0xFX18 Set Sound timer to the value of Reg X
      • 0xFX1E Add the value of Reg X to the Index Reg. [VF not affected!]
      • 0xFX29 Set the Index Reg to the location of the sprite for the character in Reg X
      • 0xFX33 Store the BCD of the value in Reg X into the Index Reg I(+0,+1,+2) = BCD(VX|3,2,1)
      • 0xFX55 Dump registers from 0 to X (inclusive) into the Index Reg I(+0,...,+X) = V(0,...,X)
      • 0xFX65 Load the Index Reg into registers from 0 to X (inclusive) V(0,...,X) = I(+0,...,+X)