[img] BBC display extensions
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Clwyd Technics Palette Extender  StarDot thread
  Clwyd Technics Palette Extender, 1983.
12-bit palette extender, plugs into the User Port. The Palette demo on the Chameleon programs disk will control the Palette Extender.
WildVision PaletteMate  pmadvert.gif
  12-bit palette extender, plugs into the Video ULA socket. Not currently known how it is controlled.
Millipede Prisma  Prisma
  Advanced video extension system, plugs into the 1MHz port.
Chameleon 12-bit palette extension  chameleon/gif
article text
Chameleon colour board, Mike Cook's version of the Clwyd Palette Extender, Micro User Feb 1990.
Palette demo on programs disk updated to also program the VideoNuLA or use native VDU 19 calls.
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.
VideoNuLA 12-bit palette extension  StarDot thread
  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.
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.
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.
LDPIC, SVPIC, RGBEDIT Graphics   Updated Acorn User LDPIC that supports 12-bit palette, and tool to edit palette files and 12-bit palette in a LDPIC file.
  PCHANGE   Palette change demo program, selects between programming the palette with native VDU 19 calls, Chameleon/PaletteExtender and VideoNuLA.
Non-complementary flashing colours  flash
  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: 10-Apr-2018