a feature request: sticky EXTEND for control combinations

[janko-jj]

If I want to do e.q. ^Q now I have to keep pressed Extend and press Q etc.

It would be nice if the pressed EXTEND could be "remembered" (even when its not pressed anymore) up until the next key is pressed.

It would allow much easier work, especially when EXTEND has to be achieved by pressing simultaneously SHIFT and SYM (e.g. on the 48K keyboard)

[taylorza]

I understand the issue with the original rubber key keyboard. The issue becomes, when do you stop remembering it was pressed. If you stop after a valid press, then it means you have to repress it for repeat operations like pasting something multiple times, I for example will copy 10 characters then paste it 8 times to get 80 chars, that becomes awkward.

I really do understand the problem, but I don't know what the best solution is.

[janko-jj]

In the current implementation, you keep EXTEND pressed while pasting eight times. I think that could be made to work even with the "stickiness" I suggest. The "stop" should not happen while EXTEND is still pressed, I suggest that the "stop" doesn't have to happen as soon as the EXTEND key is released?
It's true, in 48K Basic, once EXTEND is pressed and released, the EXTEND mode remains active, and I see that it keeps switching between [L] and [E] while the EXTEND combination remains pressed, but, as far as I understand, that's just a quirk of implementation, as, while in [E] mode (while no keys are pressed), the new press could still be implemented to cause the exit of the mode (which is what was the intention), it's just that they didn't detect that transition: I think they cleared the "new press" flag once the combination was pressed, so detecting the still pressed keys in the next frame seems to be interpreted by 48K ROM as a new press and not as still the existing combination being pressed. I believe it was done so to save a few bits of ROM or RAM (probably a programmer's decision to not compare what was pressed and is still pressed), but I think when that is not a limitation it could be done?

[taylorza]

@janko-jj - That makes sense. What I will do is add an option to the configuration, something like "sticky-extend" that will default to 0 to keep the current behavior and 1 will enable the behavior you describe.

[janko-jj]

Thanks! I think I'll also use that setting with any PC keyboard too (they also don't have Extend?). And if you implement it, something like a "^" shown somewhere in some status place during the time the "extend mode" is active would also be a nice visual feedback.
So if I was unclear my idea would be:

• Both some non-shift key or a new press on Extend key would end the "extend mode".
• Keeping Extend key pressed wouldn't cause the end of the "extend mode".
• The "extend mode" means that the single press to e.g. Q will be interpreted as ^Q.
  So almost like 48K keyboard functioned, but improved for the case when the Extend key (or the SHIFT+SYM combination) remains pressed.

[taylorza]

I shared a test binary with you on Discord. If that looks good, I will create an official release with the sticky extend capability.