-- Fully implemented all file functions, including program load and save.

-- Run/pause is working

All functions of the original MK-52 are defined:
[#]  - Comment (equivalent of NOP)
[DEG] - Degree mode
[RAD] - Radian mode
[GRD] - Degree mode
[/-/] - Negate
[Enter] - Push stack
[X<->Y]  - Swap X and Y
[+]  [-]  [*]  [/]
[Cx] - Clear X
[SIN]  [ArcSIN]
[COS] [ArcCOS]
[TG] [ArcTG]
[EXP]
[10^x]
[LG]
[LN]
[X^Y]
[LOG]
[Rotate] - Rotate stack
[X^2]
[1/X]
[SQRT]
[pi] [e]
[Bx]
[RAND] [SEED]
[[X]] - Whole part
[{X}] - Fractional par
[MAX] Max of X and Y
[|X|] - Absolute value
[SIGN] - Sign
[AND] [OR] [XOR] [NOT]
[DEG->DM] [DEG->DMS] [DM->DEG] [DMS->DEG]
[DEG->RAD] [RAD->DEG]
[mm->in] [in->mm]
[M->X ] [X->M ] [K M->X ] [K X->M ] [A M->X ] [A X->M ]
[GOTO ]
[GOSUB ]
[RETURN]
[MEMSET ] [MEMSWP ]
[ExToX ] [XToEx ] [ExToR ] [RToEx ] [MexCx]
[STOP]
[MKDIR ] [SAVE AS ] [LOAD ] [CHAIN ] [SAVE DATA AS ] [LOADDATA ]
[GOMEM ]

[IFNOT X<0 GOTO ]
[IFNOT X=0 GOTO ]
[IFNOT X>=0 GOTO ]
[IFNOT X!=0 GOTO ]
[IFNOT X<Y GOTO ]
[IFNOT X=Y GOTO ]
[IFNOT X>=Y GOTO ]
[IFNOT X!=Y GOTO ]
[WHILE L0>0 GOTO ]
[WHILE L1>0 GOTO ]
[WHILE L2>0 GOTO ]
[WHILE L3>0 GOTO ]

The remaining item is to finalize the program editor.