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Forum Index : Microcontroller and PC projects : Do we have a PicoMiteVGA image editor ?

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matherp
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Joined: 11/12/2012
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Posted: 11:09am 08 Jun 2025
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The HDMI version of the PicoMite has massive advantages over VGA especially for this sort of thing - full colour support, or stay with 16 colour but pick any 16 from 65536 using the map capability. If there were to be a simplification my vote would go for just 3, the RP2350 PicoMite, RP2350 WebMite + RP2350 HDMIUSB.
The RP2350 is completely software compatible with the RP2040, is faster, has more memory, has a better ADC and MMBasic circumvents E9. It would certainly make my life easier.
I will probably stop RP2040 development after 6.00.02. I've then got some fun ideas for the RP2350 PicoMite using a proper in-memory framebuffer and with the 2nd CPU updating the physical display in the background. I've played with this already and can get 50Hz full screen refresh rates on a SPI ILI9341. Stick a RP2350 onto the Game*Mite with this support and the opportunities are endless
 
thwill

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Joined: 16/09/2019
Location: United Kingdom
Posts: 4281
Posted: 11:24am 08 Jun 2025
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Spun off https://www.thebackshed.com/forum/ViewTopic.php?PID=240499 in the hopes of avoiding further platform discussion in this thread - sorry, I probably started it.

Tom
Edited 2025-06-08 21:24 by thwill
MMBasic for Linux, Game*Mite, CMM2 Welcome Tape, Creaky old text adventures
 
Martin H.

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Joined: 04/06/2022
Location: Germany
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Posted: 12:31pm 08 Jun 2025
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  matherp said  The HDMI version of the PicoMite has massive advantages over VGA especially for this sort of thing - full colour support, or stay with 16 colour but pick any 16 from 65536 using the map capability.

This is useful because the MAP command can also be used to display gray and brown tones. This does not change the file size. Unfortunately, this would also leave out many VGA users, which in my opinion would severely limit the distribution and acceptance of the program. One solution would be to use 2 graphics packages, one for VGA and one for HDMI.
But let's let Tom write the game first.  

Have you adjusted the load image routine so that it takes the colors from a 4-bit BMP correctly for HDMI?
Cheers
Martin
'no comment
 
Amnesie
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Joined: 30/06/2020
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Posted: 12:38pm 08 Jun 2025
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  thwill said  
  Amnesie said  do you mean something like Paint?

Look here: https://www.thebackshed.com/forum/ViewTopic.php?FID=16&TID=17589


Thanks Daniel, that is what I meant.

In that post you showed an illustration from a PicoMite(VGA?) that had been modified to allow grey in the palette though you never posted a schematic ?



Sorry, here is the schematic:


Schematic_gainta_2025-06-08.pdf



Greetings
Daniel
 
Turbo46

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Joined: 24/12/2017
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Posts: 1638
Posted: 05:53am 09 Jun 2025
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  Martin said  This is useful because the MAP command can also be used to display gray and brown tones. This does not change the file size. Unfortunately, this would also leave out many VGA users, which in my opinion would severely limit the distribution and acceptance of the program. One solution would be to use 2 graphics packages, one for VGA and one for HDMI.

I feel that the colour depth on the VGA is not great enough. If the images could be made suitable for the Pico HDMI, MMB4W, MMB4L and the CMM2 that would reach a wider audience. It's Tom's baby of course but I would choose that option with a view to later down grading the colour depth to suit the VGA version.

Who knows, there may be a 2350 VGA with greater colour depth in our future?

Speaking of an audience, how many members have actually used SAAINT to any extent? Not too many have tried it and persisted with any adventure I expect.

Bill
Keep safe. Live long and prosper.
 
phil99

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Joined: 11/02/2018
Location: Australia
Posts: 2535
Posted: 08:30am 09 Jun 2025
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  Quote  Who knows, there may be a 2350 VGA with greater colour depth in our future?
If the same number of pins used by the HDMI version are allocated to VGA the images would be better. However memory usage would increase and any extra processing time would have to fit in the refresh rate.

Assuming firmware support is practical, the existing 4 colour pins could have a selection of plugin resistor modules for different palettes. For Images matching codecs would be needed.

If firmware support isn't viable it can be done in Basic and pre-processing for images but it is a bit clumsy.
 
Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 7735
Posted: 08:57am 09 Jun 2025
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HDMI uses only two more pins than RGB121. You could, potentially, use RGB222 VGA for the same number of pins but that's still only 64 colours and you don't get the benefit of the HSTX to push the data out faster. Of course, the frame buffer is bigger to make space for the extra colour bits. So there is more data to move.

IMHO there is nothing to be gained by using VGA now other than the fact that the connector is easier to solder. If you accept that both RP2350 VGA and (poor) HDMI displays handle a maximum resolution of 640x480 then HDMI still wins hands down as the 16 available colours are mapped from RGB555 and you get the HSTX speed.
Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs
 
Bleep
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Joined: 09/01/2022
Location: United Kingdom
Posts: 609
Posted: 10:41am 09 Jun 2025
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Or simply use a very cheap, self powered HDMI to VGA dongle. Then you have all the advantages of MMBasic HDMI but on a VGA screen, with no rewiring and full MMBasic support?
 
Mixtel90

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Posted: 11:21am 09 Jun 2025
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I used one when I got my first Raspberry Pi. :)  That monitor had VGA and DVI sockets.
Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs
 
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