[OTZ80] Features - planning and FINAL chance for suggestions!!

[alberthrocks]

Hey everyone!

This topic is divided into 2 sections...

1) I need suggestions on screen size and battery type so that we can revote.
Consider the use, type, power usage, CPU's power, etc. when you specify one!

EDIT:
For screen, please specify resolution and type (color, grayscale, B/W).
For battery, please specify what type, and whether it's rechargeable or not.

2) Any other features you would like to suggest? This is your LAST chance for suggestions!
You are not allowed to specify a feature that is already voted off.

Current feature list:
CPU: eZ80 50 MHZ, underclockable to 20 MHZ
Screen size: 192x128 (7 other people voted for 240x160, revote possible based on supply and opinion change)
Battery indication: On screen (part of OS)
Navigation: regular arrow keys
ASCII input: Alpha-lock
Backlit screen: Yes... 14 vs. 9 people on this topic, may need a revote to confirm.
I/O: 3.5 mm link cable and mini USB OTG
Power: Will definitely need a revote - this was the closest one ever, with no real winner. The top two were: AA battery (rechargeable if possible), and "#1 and 2" = internal rechargeable battery + AA battery (rechargeable if possible)

Omitted features:
Wifi (too much power munching, internet connection should be external)
SD card support (no use)

[Jim Bauwens]

Any chance of adding audio to that list? It will be real cool

[ben_g]

isn't a 3.5mm I/O cable an audio jack?

and for the screen: what type? B&W, grayscale or color? I would like color with backlight, if possible.

[Jim Bauwens]

Yes, but that doesn't mean it can do audio

[Deep Thought]

Already? Awesome! I love summer vacations

Yes, but that doesn't mean it can do audio

We can always do that with ASM though. Don't want it to be too complicated/expensive.

[ben_g]

As long as that I/O port is connected in the right way to the circuit board, then you should be able to do audio in a program.

EDIT: ninja'd...

[calc84maniac]

It would be nice if the 3.5mm jack could output levels between high and low to make audio processing much, much easier. Though, for actual linking you'd probably use the high and low outputs of course.

[Jim Bauwens]

But will you be able to play full sound audio (like mp3 quality) ?

[Deep Thought]

MobileTunes quality? That seemed good enough (for me).

[alberthrocks]

isn't a 3.5mm I/O cable an audio jack?

and for the screen: what type? B&W, grayscale or color? I would like color with backlight, if possible.

For screen, please specify resolution as well. Thanks!

calc84, jimbauwens, et. al.: I think it should, given that the hardware can (and should) support it. Getting a sound chip would be a little too overkill IMO.

It would be nice if the 3.5mm jack could output levels between high and low

Hmm, it should. I'm not sure technically how this is done (software wise or HW wise), but it's definitely possible.

==========
Please reread the first post for update!

[ben_g]

isn't a 3.5mm I/O cable an audio jack?

and for the screen: what type? B&W, grayscale or color? I would like color with backlight, if possible.

For screen, please specify resolution as well. Thanks!

240 by 160 would be nice

battery: I prefer a built-in rechargable Li-ion battery. Those batteries have a very high capacity, and I like built in as it's easy too just plug it in when the battery is empty

[calc84maniac]

It would be nice if the 3.5mm jack could output levels between high and low

Hmm, it should. I'm not sure technically how this is done (software wise or HW wise), but it's definitely possible.

One way to do this is with Pulse-Width Modulation, which is somewhat similar to how grayscale is done on monochrome screens. Basically, you have some period of time (in the case of sound, it should be well under 1/20000 seconds to be outside the audible range) which is divided into, in the case of 8-bit sound, 256 cycles. For an output level X, the hardware would output low for X cycles and high for 256-X cycles. As you might imagine, it's a super pain to have to do this manually through the CPU. Dedicated hardware for this wouldn't be too hard to implement, I think.

Edit: Actually, since 8-bit values only go from 0 to 255, you'd have 255 cycles, go low for X cycles and go high for 255-X cycles.

[t0xic_kitt3n]

We could just connect the 3.5mm jack to an analog-digital converter, the various values could be used when playing sound, and then for linking, there would be a threshold value that would determine high or low.