CPU_6502_TXS.go

package CPU_6502

import "fmt"

// TXS  Transfer Index X to Stack Register
//
//      X -> SP                          N Z C I D V
//                                       - - - - - -
//
//      addressing    assembler    opc  bytes  cyles
//      --------------------------------------------
//      implied       TXS           9A    1     2

func opc_TXS(bytes uint16, opc_cycles byte) {

	// Update Global Opc_cycles value
	Opc_cycles = opc_cycles

	// Print internal opcode cycle
	debugInternalOpcCycle(opc_cycles)

	// Just increment the Opcode cycle Counter
	if Opc_cycle_count < opc_cycles {
		Opc_cycle_count++

		// After spending the cycles needed, execute the opcode
	} else {

		SP = X

		// Print Opcode Debug Message
		opc_TXS_DebugMsg(bytes)

		// Increment PC
		PC += bytes

		// Reset Internal Opcode Cycle counters
		resetIntOpcCycleCounters()
	}
}

func opc_TXS_DebugMsg(bytes uint16) {
	if Debug {
		opc_string := debug_decode_opc(bytes)
		dbg_show_message = fmt.Sprintf("\n\tOpcode %s [Mode: Implied]\tTXS  Transfer Index X to Stack Pointer.\tSP = X (%d)\n", opc_string, SP)
		fmt.Println(dbg_show_message)
	}
}