3.3.10 Z80 Options (apply to z80, z80n, z180, r2k, r3ka, tlcs90, ez80)

• [—portmode=<Value>] Determinate PORT I/O mode (<Value> is z80 or z180).
• [—asm=<Value>] Define assembler name (<Value> is rgbds, sdasz80, isas or z80asm).
• [—reserve-regs-iy] This option tells the compiler that it is not allowed to use register pair iy. The option can be useful for systems where iy is reserved for the OS. This option is incompatible with —fomit-frame-pointer.
• [—fno-omit-frame-pointer] Never omit the frame pointer.