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I'm trying to emulate it using NES Specifications and the other docs.
1º Problem
Some opcodes as: 0xBD, 0xB9, 0xB1, 0xBC, 0x79 and etc. has no fix number of cycles.
And the explanation is Add one cycle if indexing crosses a page boundary.
I'm very newbie what it means?
2º Problem
When I'm on Absolute mode addressing I merge the two operands with endianess style?
memory[cpu.programCounter+2] << 8 | memory[cpu.programCounter+1]
1º Problem
Some opcodes as: 0xBD, 0xB9, 0xB1, 0xBC, 0x79 and etc. has no fix number of cycles.
And the explanation is Add one cycle if indexing crosses a page boundary.
I'm very newbie what it means?
2º Problem
When I'm on Absolute mode addressing I merge the two operands with endianess style?
memory[cpu.programCounter+2] << 8 | memory[cpu.programCounter+1]