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| author | Mike Pavone <pavone@retrodev.com> | 2013-05-04 15:58:15 -0700 |
|---|---|---|
| committer | Mike Pavone <pavone@retrodev.com> | 2013-05-04 15:58:15 -0700 |
| commit | 703129f573b4e3b84df96612bb26db672617a8bc (patch) | |
| tree | cf1042cf399ac182bd3df92867fd61513b32955e /zruntime.S | |
| parent | d511cd2c0b128f0e5e3b55ba2d6cda1e75e49f8f (diff) | |
Implement IN and OUT (untested)
Diffstat (limited to 'zruntime.S')
| -rw-r--r-- | zruntime.S | 25 |
1 files changed, 25 insertions, 0 deletions
@@ -1,3 +1,14 @@ +z_inccycles_io: + cmp %edi, %ebp + jnb do_limit +no_sync_io: + add $4, %ebp + ret +do_limit_io: + cmp 112(%rsi), %ebp + jb no_sync_io + jmp sync_io + z_inccycles: cmp %edi, %ebp jnb do_limit @@ -7,6 +18,7 @@ no_sync: do_limit: cmp 112(%rsi), %ebp jb no_sync +sync_io: call z80_save_context_scratch pop %rax /*return address in read/write func*/ pop 104(%rsi) /*return address in native code*/ @@ -180,6 +192,19 @@ z80_write_word_lowfirst: call z_inccycles call z80_write_byte_noinc ret + + .global z80_io_read +z80_io_read: + call z_inccycles_io + /* genesis Z80 has no IO port hardware and always returns FF */ + mov $0xFF, %r13 + ret + + .global z80_io_write +z80_io_write: + call z_inccycles_io + /* genesis Z80 has no IO port hardware and writes have no effect */ + ret .global z80_retrans_stub z80_retrans_stub: |