3 ms·

I vaguely remember a device back in the day that buffered a 4 bitplane 640 pixel scanline to output a 320 pixel 256 colour mode. Seems entirely doable on a rp2

by Lerc 3y ago

I vaguely remember a device back in the day that buffered a 4 bitplane 640 pixel scanline to output a 320 pixel 256 colour mode. Seems entirely doable on a rp2040. The arm cores have so much power that there's hardy any work that you'd use the Amiga for though.

rasz 3y ago
> 4 bitplane 640 pixel scanline to output a 320 pixel 256 colour mode yeah, you are right with 320. Means no need for any soldering inside Amiga, can just plug into Video Connector like A2024 monitor, and one RP2040 is enough. > I vaguely remember a device back in the day me too! I think it was dedicated to Video processing? or maybe bundled with a scanner? and most likely required you to massage bits on computer side. Edit: found it! https://bigbookofamigahardware.com/bboah/product.aspx?id=481 https://bigbookofamigahardware.com/bboah/product.aspx?id=481 I think this https://bigbookofamigahardware.com/bboah/product.aspx?id=503 https://bigbookofamigahardware.com/bboah/product.aspx?id=503 also worked in similar way.
- boomlinde 3y ago
  There's also https://bigbookofamigahardware.com/bboah/product.aspx?id=498 https://bigbookofamigahardware.com/bboah/product.aspx?id=498
  - rasz 3y ago
    Yes! I definitely also saw this one long time ago. Most likely my "independent" idea from post above was my brain just re creating this very product from memory :] GAL, few TTLs, SRAM? and a DAC, easy and cheap to manufacture and obvious once you saw IMS G171 being released in 1986 (year before vga). Another missed opportunity by Commodore, A500 should have had a socket for INMOS G171 right on the motherboard in 1987, maybe even a flap on top of the case for easy upgrade access. Today $10 RP2040 pico board and a resistor ladder can implement it easily.
- boboche 3y ago
  You are refering to the DCTV? Was also used as a digitizer. Still got mine. Nostalgia does weird things.
  - rasz 3y ago
    Yes, DCTV! Funnily enough it turns out I followed this post all the way back in 2017: https://retrocomputing.stackexchange.com/questions/2201/how-did-the-amiga-dctv-work https://retrocomputing.stackexchange.com/questions/2201/how-... and just got email because someone updated that thread yesterday :)

by Lerc 3y ago

rasz 3y ago

> 4 bitplane 640 pixel scanline to output a 320 pixel 256 colour mode yeah, you are right with 320. Means no need for any soldering inside Amiga, can just plug into Video Connector like A2024 monitor, and one RP2040 is enough. > I vaguely remember a device back in the day me too! I think it was dedicated to Video processing? or maybe bundled with a scanner? and most likely required you to massage bits on computer side. Edit: found it! https://bigbookofamigahardware.com/bboah/product.aspx?id=481 https://bigbookofamigahardware.com/bboah/product.aspx?id=481 I think this https://bigbookofamigahardware.com/bboah/product.aspx?id=503 https://bigbookofamigahardware.com/bboah/product.aspx?id=503 also worked in similar way.

boomlinde 3y ago
There's also https://bigbookofamigahardware.com/bboah/product.aspx?id=498 https://bigbookofamigahardware.com/bboah/product.aspx?id=498
- rasz 3y ago
  Yes! I definitely also saw this one long time ago. Most likely my "independent" idea from post above was my brain just re creating this very product from memory :] GAL, few TTLs, SRAM? and a DAC, easy and cheap to manufacture and obvious once you saw IMS G171 being released in 1986 (year before vga). Another missed opportunity by Commodore, A500 should have had a socket for INMOS G171 right on the motherboard in 1987, maybe even a flap on top of the case for easy upgrade access. Today $10 RP2040 pico board and a resistor ladder can implement it easily.
boboche 3y ago
You are refering to the DCTV? Was also used as a digitizer. Still got mine. Nostalgia does weird things.
- rasz 3y ago
  Yes, DCTV! Funnily enough it turns out I followed this post all the way back in 2017: https://retrocomputing.stackexchange.com/questions/2201/how-did-the-amiga-dctv-work https://retrocomputing.stackexchange.com/questions/2201/how-... and just got email because someone updated that thread yesterday :)