Interfacing Arduino to A500 keyboard, general question

Hi all,

I want to interface the Arduino to an Amiga 500 keyboard. However, the question might be more general:

The Amiga's keyboard interface consits of Clock and Data lines, where a handshake signal is expected from the Arduino via Data. This probably means Data is bidirectional. Would it be a good approach to connect Data directly to an input line, and via diode and resistor to an output line from the Arduino?

I've thus far tried to use a single line, directly connected, switching from Input to Output state, and may have fried something (don't know). Anyway, it didn't work. My next try should be successful, if all has survided my attempts to kill it.

2nd: There's a hardware reference manual, mentioning Clock is an active low signal. Does this mean a '1' is represented by 0V and a '0' by 5V? Or did I got this completely wrong?

Please bear with a beginner :-).

Thanks,

thradtke

thradtke:
2nd: There's a hardware reference manual, mentioning Clock is an active low signal. Does this mean a '1' is represented by 0V and a '0' by 5V? Or did I got this completely wrong?

Hi Thradtke,

According to this page the data line acts as you say. When you're looking at a clock signal, treating it as 1 or 0 isn't really necessary as it's really the change in state and the duration in each state that matters - ie you're not forming a binary value of 0's and 1's.

From that page,

The KDAT line is active low; that is, a high level (+5V) is interpreted as 0, and a low level (0V) is interpreted as 1.

Cheers, and good luck with your project ! Geoff

Thanks, Geoff!

Maybe a moderator could merge both my threads. I shouldn't have created two in the first place. Sorry for that :-(.