Wow! That is quite an achievement 
Next step is to add a keyboard connector & BASIC. And then weāve got ourselves a nice little home computer 
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Iād be happier with just being able to play Pokitto games on a large monitor,
even if a hat was needed to be able to do it at a decent speed.
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Thatās actually what I am after as well. The implementation I have done here leaves the second timer completely free. This means sound playback etc could still be done at the same time. Iām not saying this is leading to a Pokitto console but its ever so faintly pointing in that direction.
A 10ā¬ hat that could do this would be pretty cool wouldnāt it?
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Maybe you are building an IchigoJam-basic brainā¦
Ichigo need a screen output, sound output, keyboard input and maybe a few GPIO.
They do it on custom hardware, and the Raspberry Pi.
But having a HAT connected to the Pokito to transform it into a TV Computer (like 25-30 years ago) would be great achievement.
That would be like the Switch that you can play while plugged to the screen or on the go.
I was at the workshop just now, assembling Pokittos for a new order.
While I was there, I tried a new approach.
Result 220x480 @ 8 colors stable.
From a standard Pokitto, through the PEX header.
Didnt have time for pictures/video
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Erinomainen! EdistystƤ!
Doesnāt that mean that 220x240@ 16 colours should be theoretically possible?
(Iām expecting thereās a technical reason why it wonāt work, involving timing or something.)
The VGA signal is a funny thing because it is analog. So the way I do it now I have 3 signal lines and I mask them out. So R = 0x1, G = 0x2, B = 0x4, RG (yellow) = 0x3, RB (pink) = 0x5, GB (cyan) = 0x6, RGB (white) = 0x7.
If we want more colours, those signal lines need to be āsplitā into several levels of voltage between 0ā¦0.7V by using, for example, a resistor ladder.
So then we would have 6 lines for color: R,G,B,R/2,G/2,B/2. This allows 2^6 = 64 colors.
So technically yes, at least 64 colors seems feasible relatively easily.
On the code side it is already using 8 bits for color. So that does not limit
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Sinclair in your pocket?
Seriously how hard would it be to make pokitto emulate a spectrum? Or would need a little keyboard and it could be the ram pack stuck to the back lol
I would assume itās reasonably hard.
Hereās a spec comparison:
| Spec | Pokitto | ZX Spectrum |
|---|---|---|
| Architecture | ARM Cortex M0+ | Intel 8080 (Modified) |
| CPU | LPC11U68 | Zilog Z80 |
| Frequency | 48 MHz | 3.5 MHz |
| Progmem/ROM | 256 KB | 16 KB |
| RAM | 36 KB | 16 KB/48 KB/128 KB |
| Resolution | 220x176/110x88 | 256x192 |
The CPU power isnāt an issue,
but it would definitely need an external display,
and the Pokitto has less RAM than the 48 KB and 128 KB models.
Tangentially relatedā¦
In 2012 it was the spectrumās 30th anniversary, so Google did this:
(It was also St. Georgeās day in case anyone couldnāt tell from the knight and the dragon. :P)
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