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Forum Index : Microcontroller and PC projects : PicoMiteHDMI framebuffer thoughts
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Mixtel90 Guru  Joined: 05/10/2019 Location: United KingdomPosts: 7879 |
Hmmm... Dunno... The RP2350 isn't using a PIO for video generation, but whether that makes any difference I don't know. Only having half the RAM certainly *will* make a difference as there isn't room to increase the size of the framebuffer. I assume that there's some RAM required to handle the magic colours. Mick Zilog Inside! nascom.info for Nascom & Gemini Preliminary MMBasic docs & my PCB designs |
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| Bleep Guru Joined: 09/01/2022 Location: United KingdomPosts: 625 |
The HSTX isn't simply a very fast parallel to serial converter, you can insert in the data path an extra bit of logic called a command expander, which I suspect is what is helping to do the colour mapping, so probably not, & I'm probably completely wrong, but who knows. ;-) There also is something called a TMDS Encoder, in the SIO logic, which may also be responsible? Regards Kevin. Nope wrong, looks like Peter is doing it all on the second core. "I've got the HSTX example working nicely and have moved the processing onto the second core. I'm using two linebuffers which one of which is filled while the other is being output rather than outputting from the framebuffer direct. This allows me to do things like merge a top layer over a background layer in the code and then move that composite to the line buffer when required. I also use mapping arrays so a framebuffer that is 640x480x4bits can be mapped to any of 256 colours." Edited 2024-08-19 06:34 by Bleep |
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| matherp Guru Joined: 11/12/2012 Location: United KingdomPosts: 10251 |
UPDATE I couldn't get RGB565 or RGB555 working  HOWEVER RGB888 is working nicely  This means that all mapping tables now allow any of the colours to be mapped to a full RGB888 value allowing things like 256 grey shades and a new mode 6 - 320x240x1677721 colours. This is still just standalone HSTX testing with no integration with MMBasic so I could hit some bus bandwidth issues but so far so good Edited 2024-08-19 20:36 by matherp |
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| Mixtel90 Guru Joined: 05/10/2019 Location: United KingdomPosts: 7879 |
This is getting silly..... :D Mick Zilog Inside! nascom.info for Nascom & Gemini Preliminary MMBasic docs & my PCB designs |
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| PhenixRising Guru Joined: 07/11/2023 Location: United KingdomPosts: 1362 |
I like silly   |
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