
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

The Interface Hooked Up to
an Apple II on One End - a PS/2 Keyboard and a PC via RS232 on the Other
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