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    This window is used to display the trace buffer. Selecting an execution step from this window causes the source listing and disassembler windows to be positioned at the relevent instruction. This window is divided into columns allowing the user to selectively hide unintresting information. This window is also used to show debug information generated by the simulator. Debug information is stored in the trace buffer together with the CPU state change information in strict execution order. The debug information will consequently always correspond to the CPU state after which it apears.
    The fields of the execution trace are:
    1. CPU clock cycle
    2. program counter (location from which opcode was fetched)
    3. hex value of machine code fetched
    4. assembler nmemonic corresponding to machine code fetched
    5. destination register e.g. f21, w (in the case where the machine code does not modify the register, then this is the source register e.g. BTFSS)
    6. the original value of the destination register
    7. the final value of the destination register
    8. condition code register if modified
    9. port A if modified
    10. port B if modified