- add additional key matrix connector (for custom matrix including Apple 2)
- Fix bypassed diodes. Diodes on rows 8-15 should have been
- jumpered (bypassed), but instead were standard diode footprints.
Provides a keyboard interface to interface with OSI computers. Equivalent to an
OSI 542C.
- Includes sound circuits
- Includes RESET delay circuit
- SHIFT LOCK can be mechanical push-on/push-off or soft toggle, selectable by
jumper.
- Provide SHIFT LOCK LED output.
- This allows the PCB to sink below the mounting brackets. The aligner height can
be adjusted relative to the mounting brackets using spacers.
- changed futaba aligners to use cherry stabilizers.
- bumped rev number
For better matching of current limit resistors to LEDs, the resistors are moved
to the keyboard matrix PCB, where they can be tuned for maximum brightness (at
100% duty cycle). This allows consistent keyboard brightness when a single
interface PCB is swapped between keyboard matrices.
- Fixed position offset error in first three rows of the SOL keyboard
- moved key matrix interface connector to bottom of board so the parallel output
connector can be at the top of the keyboard.
- Adjusted size of mounting slots to accommodate #6 screws.
- ongoing clean up of traces.
This allows the keymap to determine which LED is used, rather than requiring the
decision to be hardwired in at the time of assembly. For the OSI keyboard, the
LED could be placed on the SHIFTLOCK key, at the far right LED, or in the
CAPSLOCK position, which is just to the left of the RETURN and not otherwise
populated in the OSI layout.
- swap numbering of row select protection diodes for cleaner PCB labeling
- clarify labeling on GPIO pins on the MCU
- bump rev to 2.4 to indicate work in progress. Release will be 2.5.
