Keyboard interface software
Added 2021-04-03 07:32:45 +0000 UTCThanks everyone for the feedback on the last video. I appreciate the thoughts in both directions on splitting up the video. The comments that resonated most with me were that the software part felt rushed—I agree. I was trying to squeeze everything into one video, intentionally went through it quickly, and feared it would seem rushed. I got enough comments confirming that fear. So the plan is to add some more detailed explanations of what's going on and add a little more functionality (like handling the shift key).
I just edited the previous post to now link to the final version of the video. So in case you missed it, here's a link to what I cut from that video: https://youtu.be/dstWaNrNgaY
I hope to have a better version of that out in a week or so. Thanks again for your feedback and support.
-Ben
Comments
What happened to the E,RW,RS signals for the lcd and interface adapter, I don't see them being hooked up?
2022-04-10 21:06:27 +0000 UTCcan't you use PHX ( opcode DA) and PLX (opcode FA)?
Michael McDonnell
2021-04-12 21:15:29 +0000 UTCmayby detect that it is an 'extended' code and not reset the release flag just yet
2021-04-08 17:29:04 +0000 UTCThis RELEASE flag is a nice thing, but when we have multi byte scan codes (like home) it only ignores the first byte.
2021-04-08 17:28:19 +0000 UTCDo you plan on covering what the internals of the keyboard are doing, like how its generating its clock and data lines and whatnot?
Michael Maxwell
2021-04-08 15:40:12 +0000 UTCThe pointers should automatically wrap, but an explicit explanation here might not hurt.
Amos Bannister
2021-04-03 19:25:03 +0000 UTCMy Apple II nostalgia thanks you for putting the keyboard buffer at $0200 (even if on the Apple II the keyboard was neither interrupt driven, nor had a circular buffer).
Mark Day
2021-04-03 16:34:58 +0000 UTCI didn't notice it in the first edit, but when you wrote the keyboard buffer pointers, around 33s in this video (around a subtle edit), the kb_rptr is changed to address $0100 . I was confused by this, because it's also the stack address. Later (around 6m50) when we see this bit of code in the video again, it is set back to $0001.
Remco van Zuijlen
2021-04-03 10:21:51 +0000 UTCOne thing I meant to mention in the last video: do you handle getting to the end of the buffer? My guess is the X register is 8 bits wide so the buffer index auto-wraps, but I didn't hear you mention it (I might've just been distracted).
Rick Mann
2021-04-03 09:23:13 +0000 UTC
