The Yamaha V9958 is a Video Display Controller

Video Display Controller

A Video Display Controller or VDC is an integrated circuit which is the main component in a video signal generator, a device responsible for the production of a TV video signal in a computing or game system...

 (VDC) used in MSX

MSX

MSX was the name of a standardized home computer architecture in the 1980s conceived by Kazuhiko Nishi, then Vice-president at Microsoft Japan and Director at ASCII Corporation...

 80s

1980s

File:1980s decade montage.png|thumb|400px|From left, clockwise: The first Space Shuttle, Columbia, lifted off in 1981; American President Ronald Reagan and Soviet leader Mikhail Gorbachev eased tensions between the two superpowers, leading to the end of the Cold War; The Fall of the Berlin Wall in...

 home computers. More specifically, the "TIM" upgrade to the TI-99/4A, MSX 2+ and MSX turbo R.

The Yamaha V9958, also known as MSX-Video, is the successor of the Yamaha V9938

Yamaha V9938

The Yamaha V9938 is a Video Display Controller used in the Geneve 9640 enhanced TI-99/4A clone, as well as MSX 80s home computers ....

 (used in the Myarc Geneve 9640

Geneve 9640

-Geneve 9640:The Geneve 9640 is an enhanced TI-99/4A clone which was built by Myarc as a card to fit into the TI Peripheral Expansion System and used an IBM PC XT detached keyboard as well as a mouse. Released in 1987, it was in many ways similar to the earlier TI-99/8 which was in prototype form...

 upgrade for the TI-99/4A and the MSX2

MSX2

MSX2 may refer to:* Msh homeobox 2, a human gene* The second generation of the MSX home computers...

). It was generally conceived not to be a very major upgrade to its predecessor, which hampered its adoption. The main new features are three graphical YJK modes (with up to 19268 colours) and horizontal scrolling registers.

Specifications

• Video RAM: 128 KB + 64 KB of expanded VRAM
• Text modes: 80 x 24 and 32 x 24
• Resolution
  Display resolution
  The display resolution of a digital television or display device is the number of distinct pixels in each dimension that can be displayed. It can be an ambiguous term especially as the displayed resolution is controlled by all different factors in cathode ray tube , flat panel or projection...
  
  : 512 x 212 (16 colours out of 512) and 256 x 212 (19268 colours)
• Sprites
  Sprite (computer graphics)
  In computer graphics, a sprite is a two-dimensional image or animation that is integrated into a larger scene...
  
  : 32, 16 colours, max 8 per horizontal line
• Hardware acceleration
  Hardware acceleration
  In computing, Hardware acceleration is the use of computer hardware to perform some function faster than is possible in software running on the general-purpose CPU...
  
   for copy, line, fill, etc.
• Interlacing to double vertical resolution
• Horizontal and vertical scroll registers

Detailed specifications

For detailed specifications, please refer to the Yamaha V9938

Yamaha V9938

The Yamaha V9938 is a Video Display Controller used in the Geneve 9640 enhanced TI-99/4A clone, as well as MSX 80s home computers ....

 page, with the following additions:

• Horizontal scrolling registers
• YJK graphics modes (similar to YUV
  YUV
  YUV is a color space typically used as part of a color image pipeline. It encodes a color image or video taking human perception into account, allowing reduced bandwidth for chrominance components, thereby typically enabling transmission errors or compression artifacts to be more efficiently...
  
  )
  • G7 + YJK + YAE: 256 x 212, 12499 colours + 16 colour palette
  • G7 + YJK: 256 x 212, 19268 colours
• Ability to execute hardware accelerated
  Hardware acceleration
  In computing, Hardware acceleration is the use of computer hardware to perform some function faster than is possible in software running on the general-purpose CPU...
  
   commands in non-bitmap screen modes
• Lightpen and mouse functions from V9938 were removed

MSX-specific terminology

On MSX, the screen modes are often referred to by their assigned number in MSX-Basic. This mapping is as follows:

Basic mode	VDP mode	MSX system
Screen 0 (width 40)	T1	MSX 1
Screen 0 (width 80)	T2	MSX 2
Screen 1	G1	MSX 1
Screen 2	G2	MSX 1
Screen 3	MC	MSX 1
Screen 4	G3	MSX 2
Screen 5	G4	MSX 2
Screen 6	G5	MSX 2
Screen 7	G6	MSX 2
Screen 8	G7	MSX 2
Screen 10	G7 with YJK and YAE	MSX 2+ and tR
Screen 11	G7 with YJK and YAE	MSX 2+ and tR
Screen 12	G7 with YJK	MSX 2+ and tR