Apple-2-HW/micro-sci-a2-controller
1
0
Fork 0
mirror of https://codeberg.org/cryu/micro-sci-a2-controller synced 2024-06-19 14:29:31 +00:00
Code Issues Packages Projects Releases Wiki Activity
eb26141a55
micro-sci-a2-controller/README.md
Christopher RYU 525cd5491d Documentation cleanup.
2023-07-19 12:02:28 +09:00

1.3 KiB
Raw Blame History

Micro-SCI / Franklin Apple ][ Floppy Drive Controller

This is a clone of the Micro-SCI / Franklin floppy drive controller.

v0.1 is a direct clone, reverse-engineered from a Micro-SCI board. It was cross-checked with a Franklin-branded board, as well as the (belatedly discovered) official Franklin schematic (included in doc/service_and_schematics.pdf)

v0.2 has the following enhancements over the original design:

  • the 2708 EPROM has been replaced with a more-common 2716/2732 EPROM
  • decoupling capacitors have been added
  • footprints for all capacitors and resistors have been modernized
  • firmware EPROM bank selection jumpers replaced with a DIP switch
  • obsolete MPS-U51 transistor replaced with modern equivalent
  • clearly-marked calibration test points have been added
  • ground pours used to increase operational stability
  • support for using Floppy Emu in dual-drive emulation mode with one cable

Firmware images can be built via the Makefile in the firmware subdirectory. The build framework requires cc65.

usci

EPROM bank select switches (J4)

  • 1:off 2:off - controller test firmware (0x0000)
  • 1:off 2: on - 16-sector firmware (0x0100)
  • 1: on 2:off - 13-sector firmware (0x0200)
  • 1: on 2: on - firmware "put jumpers here" splash screen (0x0300)