52 lines
946 B
NASM
52 lines
946 B
NASM
; *** Variables ***
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.equ IO_IN_GETC IO_RAMSTART
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.equ IO_IN_PUTC IO_IN_GETC+2
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.equ IO_IN_SEEK IO_IN_PUTC+2
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.equ IO_IN_TELL IO_IN_SEEK+2
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.equ IO_OUT_GETC IO_IN_TELL+2
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.equ IO_OUT_PUTC IO_OUT_GETC+2
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.equ IO_OUT_SEEK IO_OUT_PUTC+2
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.equ IO_OUT_TELL IO_OUT_SEEK+2
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; see ioPutBack below
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.equ IO_PUTBACK_BUF IO_OUT_TELL+2
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.equ IO_RAMEND IO_PUTBACK_BUF+1
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; *** Code ***
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ioInit:
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xor a
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ld (IO_PUTBACK_BUF), a
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ret
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ioGetC:
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ld a, (IO_PUTBACK_BUF)
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or a ; cp 0
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jr nz, .getback
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ld ix, (IO_IN_GETC)
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jp (ix)
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.getback:
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push af
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xor a
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ld (IO_PUTBACK_BUF), a
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pop af
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ret
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; Put back non-zero character A into the "ioGetC stack". The next ioGetC call,
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; instead of reading from IO_IN_GETC, will return that character. That's the
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; easiest way I found to handle the readWord/gotoNextLine problem.
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ioPutBack:
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ld (IO_PUTBACK_BUF), a
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ret
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ioPutC:
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ld ix, (IO_OUT_PUTC)
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jp (ix)
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ioSeek:
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ld ix, (IO_IN_SEEK)
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jp (ix)
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ioTell:
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ld ix, (IO_IN_TELL)
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jp (ix)
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