The Apple IIGS got incredibly good Apple IIe compatibility, including precise timing for Disk II and other hardware interfacing, by hardcoding all the bank switching and Apple II stuff that Woz originally implemented in 74-series logic chips, in a single Apple II ASIC, with another ASIC for the bus management, and it had logic to drop down to 1 MHz whenever accessing the original 2 x 64K banks of a 128K Apple IIe or the I/O or ROM space in those address ranges.
The other 64K banks are "fast".
jhamby
npub17q…c5ajl
2024-12-28 19:44:31 UTC
in reply to nevent1q…zwge
Author Public Key
npub17qjwcdn3ss4t4kzn6anc0l53zl4p9t5qtf96tsdgwakznzg4s57q7c5ajlSeen on
wss://relay.momostr.pinkPublished at
2024-12-28 19:44:31 UTCEvent JSON
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