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diff --git a/f65/README b/f65/README deleted file mode 100644 index 0f7d0a3..0000000 --- a/f65/README +++ /dev/null @@ -1,32 +0,0 @@ -f65 - "fake 6502" porting layer - -This is a set of C macros that implements most of the 6502 assembly -language instructions, plus a perl script to convert 6502 assembly -source to C code that calls the macros. You can use it to assist in -porting 6502 assembly routines to C, using either the original asm -source, or a disassembly created with da65. - -What's implemented: 64K of memory. The A/X/Y/S registers. The carry, -zero, and negative flags. Most arithmetic and logic instructions. The -stack. Conditional branches and absolute jumps are implemented as C -goto's. JSR is implemented as a real C function call, and RTS is a -real C return. Labels in the assembly source become C labels (aka goto -targets). Equates in the asm source become C variables. - -What's not implemented: The D flag, and decimal mode in general. The -V flag, and branches based on it. The I and B flags. Interrupts -and the RTI instruction. The Program Counter (though branches, JMP, -JSR, and RTS are implemented without it). ROM routines (including -I/O). Indirect JMP. The "CPU bug" that causes e.g. 'LDA ($FF),y' to -take its high byte from $00 rather than $100. (zeropage, x) addressing -mode. - -I wrote this specifically to port the decompression algorithm from -UnAlf 1.4. Instructions not used by UnAlf probably aren't implemented, -or if they are, they're untested. - -The perl script doesn't magically convert a whole 6502 program to C -source. You'll have to figure out which parts of the 6502 program are -subroutines, and put them in their own C functions. Any data (.byte, -.word, etc) won't be in the C program. Anything that does I/O must be -rewritten in C. |