ASCII to PS/2 Keyboard Interface

This board converts either a PS/2 keyboard input or RS232 input into a Apple II compatible ASCII (or other vintage computer) keyboard interface.  Initial prototype (pictured here) is currently operating.  Let me know if you are interested in obtaining one of these.  Depending upon interest, I may make a small production run of these units in kit form (estimated cost at this time would be around $25-$35). Cost would be depend greatly upon number of boards produced, if any.

For now I will provide BOM,  FW listing and board layout for non-commericial purposes for those of you who can home brew your own PC boards and program your own AVR micro-controllers.  Just send me an email stating that you are not going to use this information for commercial purposes and I'll send you what you need to build your own PS/2 to ASCII keyboard interface.

Current Features

• Use a regular PS/2 keyboard on Apple II or other vintage computer that accepts ASCII keyboard input
• Upper and lower case support
• Support PS/2 numeric keypad (numeric mode only - cursor controls will not work)
• Use PC terminal program (hyperterm) running on modern PC, for vintage computer input device
• Echos PS/2 keyboard input to RS232 TX for input logging purposes
• cntrl-R - cntrl-S - cntrl-T reset sequence pre-programmed
• You can use terminal programs on a PC to send scripts of commands to target computer keyboard input interface
• Can be adapted to other vintage micro-computers by rewiring connection to target PC
• Operates from +5 volt supply (amperage requirements to be determined shortly)
• RS232 runs at 9600 baud
• Shift lock support  - sending commands to change the LED status on the keyboard is trickier than one might imagine, but I finally have it working
• Arrow mapping to Apple esc-char cursor movement (apple specific)
• Cntl-Alt-Del reset support

Future Features (requiring new PCB layout)

These features will improve compatibility with Apple 1 and other early micro-computers requring an ASCII keyboard interface.  I have already laid out. but not built, this new board.  It will allow easy reconfiguration of the 16 pin socket and has jumper configuration for changing data and strobe levels.  Since I personally don't have a need for one of these enhanced cards, I will put the project  on hold until I determine that enough folks are interested in purchasing boards.  Building a prototype with the new layout would take away from other projects that I have in the pipeline.  Also, the expense of making a run of cards is quite high.  Until I determine that there is sufficient interest, I'm putting this project on hold.

• Easily jumperable keyboard 16 pin socket pinout - will allow apple 1 and other vintage computers with DIP16 header connections to use straight through ribbon cable connection
• High going strobe support
• Inverted data level support
• Clear screen strobe support (apple 1)

This Project was Inspired by Other Peoples Work

• http://seb.riot.org/appleII/keyboard.sml
• http://www.scienceprog.com/wp-content/uploads/2006/08/AVR313.pdf
• http://www.brielcomputers.com/wik/index.php?title=SuperE

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