63 lines
1.5 KiB
Go
63 lines
1.5 KiB
Go
package chip8
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func (emulator *Emulator) ClearScreen() {
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// TODO: clear the screen buffer
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emulator.PC += InstructionSize
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}
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func (emulator *Emulator) Return() {
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emulator.StackPop()
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}
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// Jump to location nnn.
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//
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// The interpreter sets the program counter to nnn.
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func (emulator *Emulator) Jump(nnn uint16) {
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emulator.PC = nnn
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}
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// Call subroutine at nnn.
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//
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// The interpreter increments the stack pointer, then puts the current PC
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// on the top of the stack. The PC is then set to nnn.
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func (emulator *Emulator) Call(nnn uint16) {
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emulator.StackPush()
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emulator.PC = nnn
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}
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// Skip next instruction if Vx = kk.
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//
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// The interpreter compares register Vx to kk, and if they are equal,
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// increments the program counter by 2.
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func (emulator *Emulator) SkipEqual(x uint8, kk uint8) {
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if emulator.V[x] == kk {
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emulator.PC += InstructionSize * 2
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} else {
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emulator.PC += InstructionSize
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}
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}
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// Skip next instruction if Vx != kk.
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//
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// The interpreter compares register Vx to kk, and if they are not equal,
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// increments the program counter by 2.
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func (emulator *Emulator) SkipNotEqual(x uint8, kk uint8) {
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if emulator.V[x] != kk {
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emulator.PC += InstructionSize * 2
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} else {
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emulator.PC += InstructionSize
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}
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}
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// Skip next instruction if Vx = Vy.
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//
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// The interpreter compares register Vx to register Vy, and if they are equal,
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// increments the program counter by 2.
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func (emulator *Emulator) SkipRegistersEqual(x uint8, y uint8) {
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if emulator.V[x] == emulator.V[y] {
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emulator.PC += InstructionSize * 2
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} else {
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emulator.PC += InstructionSize
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}
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}
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