Nobody develops super, available, and not expensive card onto the A500 machine. Min.: IDE controller 2 MB/s with CF card, 2 CF slot, 68000 30-50 MHz or 68020 (not 68EC020) 14-33 MHz CPU, 8 MB fastRAM + 1 MB chipRAM (to rev. 5 and 6A motherboards), 2 CF socket, inbuilt 1.3+3.1 KS switcher, etc.
These developments did not reach the stage of the distribution.
1-- Zeus68K = They never finish it (because of the ACA500).
68SEC000 CPU running at 7 or 50 MHz, 8 MB RAM, 1 x BootMenu (Config), 6 x Kickstart ROM Switcher, IDE Controller (Gayle Logic A600), Clock Port, Realtime Clock, Freezer Button.
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2-- HC508
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68HC000 CPU running at 50 MHz (100% MC68000 compatible)
40 pin IDE connector for HDD, CD ROM etc.
Integrated CF card connector
8 MB Fast RAM (1 wait state)
512k FlashROM for Kickstart (1 wait state)
Utility for disabling / enabling every module separately (XCPU, XRAM, XROM, IDE)
What kind of developments are yet onto A500?
They will be the lonely developers in disadvantage always opposite the bigger firms.