[img] BBC display extensions
MDFS::Info.Comp.BBC.Display Search

Clwyd Technics Palette Enhancer  Clwyd
Enhancer.jpg
clwyd.ssd
StarDot thread
  Clwyd Technics Palette Enhancer, 1983.
12-bit palette extender, plugs into the User Port but is controlled slightly differently to the Chameleon. See Control.
CTS Recognition Colour Card 500  CTSPalette
CC500.jpg
advert.gif
article.gif
  12-bit palette extender, plugs into the 1MHz bus, and also gives an additional 6522 VIA user port.
"The Plus card from CTS Recognition gives users the choice of eight colours in mode 2 from a palette of 4096 hues."
WildVision PaletteMate  pmadvert.gif
WildVision
  12-bit palette extender. From the advert it appears to be the same technology as the Clwyd Technics and Chameleon palette extender, "the actual changed colour can be changed", "plugs into... the standard connector at the rear of the BBC." However, adverts also say "allows 16 colours to be used", so suggests it bypasses or supplements the video ULA, as in Beebug 5 October 1986:
"Wild Vision's Palettemate board allows 16 colours to be selected from 4096 in MODE 2."
Millipede Prisma  Prisma
Manual
  Advanced video extension system, plugs into the 1MHz port.
Chameleon 12-bit palette extension  Chameleon chameleon/gif
chamel1.txt
chamel2.txt
chamel.ssd
 
schematic
article text
 
programs
Chameleon colour board, Mike Cook's version of the Clwyd/PaletteMate palette extender, Micro User Feb 1990.
The PCHANGE palette control program updated to also program the Clwyd, CTS CC500, VideoNuLA and native VDU 19 calls.
Saturn FX  Saturn
 
   
VideoNuLA 12-bit palette extension  VideoNuLA
StarDot thread

YouTube
  Rob Coleman's VideoNuLA replacement Video ULA provides a 12-bit palette in a similar manner to the WildVision PaletteMate, and also provides extended screen MODEs.
The palette can be programmed with the updated PCHANGE Chameleon palette control program.
YouTube video demonstrating software and hardware MODE extensions.
This uses the v1.02+ nULA drivers, patched to put the MODE numbers in the standard VDU order.
PCHANGE palette programming demo PCHANGE (L)   Chameleon palette programming demo program, updated to allow programming the palette with native VDU 19 calls, the Clwyd, CTS CC500, Chameleon and VideoNuLA. Tube compatible.
Palette documentation Palette   Palette control information.
LDPIC, SVPIC, RGBEDIT Graphics   Updated Acorn User LDPIC that supports 12-bit nULA palette, and tool to edit palette files and 12-bit palette in a LDPIC file.
Border colour module Border   A small module that plugs into the Video ULA socket and provides a programmable border colour at location &FE22. b0-b2 are written with the 3-bit RGB colour, written as %00000bgr.
Extended BBC screen MODEs  NewModes   Extended screen MODEs for BBC/Master. MODEs 8-14 with twice the colour depth of MODEs 0-6.
YouTube video demonstrating software MODE extensions.
VDU19 API vdu19.txt   VDU19 API specification. Any code to provide extensions to VDU19 must follow this API.
VDU19 extension vdu19.src   Source code to extend VDU 19 to program the Chameleon or VideoNuLA to select 12-bit RGB colours, and to select border colours.
  Colours   Physical colours and colour numbers.
  MODEs   Screen MODEs.
Non-complementary flashing colours  flash (L)
flash.gif
flash.src (L)
  Short program to demonstrate flashing colours between any two colours (eg blue/green, black/red, etc), not just between complementary colours (eg blue/yellow, black/white, etc.).
Source code to create VDU 19 extension to implement VDU 19,l,32+n,0,0,0 and VDU 19,l,48+n,0,0,0 to set flash colours independently.

Authored by J.G.Harston
Last update: 21-May-2020