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Forum Index : Microcontroller and PC projects : PicoMiteVGA: Wish List
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| matherp Guru  Joined: 11/12/2012 Location: United KingdomPosts: 9129 |
You are missing the point about the VGA output. You have 16 "colours" available. These can be anything depending on the resistor/gate network used. 16 shades of light grey OK. 8 shades of red and 8 of green OK. RGB121 - as per the manual - of course. You could even select the current pallette using other output pins. The only limitation is that it is not practical to swap pallette in a frame. In the software you would just have to name the 16 levels in the pallette to match your electronics. |
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Mixtel90 Guru Joined: 05/10/2019 Location: United KingdomPosts: 6798 |
It should be pretty close. The end result will depend on how well the output stage is matched to the inputs of the display. You should get 16 grey levels, including black and white pn a Mode 2 320x240 display. If you want to play with 640x480 you'll still be restricted by the tile system. The techy bit: The inputs will be 75R each, so the load on the output stage will be 75/3 = 25R and 0.7V for full white brightness. That's 28mA from the output stage. I'd go for an emitter follower. Because of the base-emitter voltage drop it would need a maximum input voltage of about 0.65+0.7 = 1.35V. That's well within the capability of a PicoMite R-2R DAC. Mick Zilog Inside! nascom.info for Nascom & Gemini Preliminary MMBasic docs & my PCB designs |
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ice2642 Regular Member  Joined: 27/05/2023 Location: BrazilPosts: 82 |
Hello More 1 item for the wish list. Layout PT-BR (ABTN-2) for the keyboard. Or US international with dead keys, for "ç" "ã" "ê" "ô" "ó" will be very helpful. For example, > option keyboard pt-br or > option keyboard us-int Best regards, MMBasic 5.0707 on PicoMite VGA |
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| Mixtel90 Guru Joined: 05/10/2019 Location: United KingdomPosts: 6798 |
I think there are problems with multi-code keys. If you need special characters you will, as a minimum, need to let matherp know the exact code sequence to be sent and which key sends it. I don't think it's always possible. Even if the keys can be handled there are limits on which characters can be displayed as many ASCII codes are used internally by MMBasic. Mick Zilog Inside! nascom.info for Nascom & Gemini Preliminary MMBasic docs & my PCB designs |
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| ice2642 Regular Member Joined: 27/05/2023 Location: BrazilPosts: 82 |
Does MMBasic not accept 16-bit unicode? I'm still reading the manual following it slowly testing part by part, so slowly, I don't know much detail yet. excuse my ignorance. Best regards, and tkz for answer. MMBasic 5.0707 on PicoMite VGA |
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TassyJim Guru Joined: 07/08/2011 Location: AustraliaPosts: 6100 |
MMBasic is NOT Unicode or UTF8 aware. MMBasic strings are ASCII 7 bit only. You can print any character up to chr$(254) using a font with the desired characters in it. You have to use CHR$(n) or for some versions of MMBasic, C type escape characters are possible. Jim VK7JH MMedit MMBasic Help |
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