Video Display Controller

A Video Display Controller or VDC is an dent ambit which is the capital basic in a video arresting generator, a accessory amenable for the assembly of a TV video arresting in a accretion or bold system. Some VDCs additionally accomplish an Audio signal, but in that case it's not their capital function.

VDCs were best generally acclimated in the old home-computers of the 80s, but additionally in some aboriginal video bold systems.

The VDC is consistently the capital basic of the video arresting architect logic, but sometimes there are additionally added acknowledging chips used, such as RAM to authority the pixel data, ROM to authority appearance fonts, or conceivably some detached argumentation such as about-face registers were all-important to body a complete system. In any case, it's the VDC's albatross to accomplish the timing of the all-important video signals, such as the accumbent and vertical synchronisation signals, and the blanking breach signal.

Most generally the VDC dent is absolutely dent in the argumentation of the capital computer system, (its video RAM appears in the anamnesis map of the capital CPU), but sometimes it functions as a coprocessor that can dispense the video RAM capacity independently

Video shifters

The RCA CDP1861 was a actual simple chip, congenital in CMOS technology (which was abnormal for the mid '70's) to accompaniment the RCA 1802 microprocessor, it was mainly acclimated in the COSMAC VIP. It could alone abutment a actual low resolution connected clear mode.

The "Television Interface Adapter (TIA) is the custom video dent that is the affection of the Atari 2600 amateur console, a actual archaic dent that relied on the 6502 dent to do best of the work, additionally was acclimated to accomplish the audio

CRT Controllers

The Intel 8275 CRT ambassador was not acclimated in any boilerplate system, but was acclimated in some S100 bus systems.

The Motorola 6845 is a video abode architect aboriginal alien by Motorola and acclimated for the Amstrad CPC, and the BBC Micro. It was after acclimated for about all the aboriginal video adapters for the PC, such as the MDA, CGA and EGA adapters. In all after VGA accordant adapters the action of the 6845 is reproduced central the Video Chip, so in a faculty all accepted IBM PC accordant PC's still absorb the argumentation of the 6845 CRTC

Video Interface Controllers

The Signetics 2636 and 2637 are video controllers best accepted for their use in the Interton VC 4000 and Emerson Arcadia 2001 respectively.

The MC6847 is a video affectation architect (VDG) aboriginal alien by Motorola and acclimated in the TRS-80 Color Computer, Dragon 32/64, Laser 200 and Acorn Atom amid others.

The MOS Technology 6560 (NTSC) and 6561 (PAL) are accepted as the Video Interface Controller (VIC) and acclimated in the Commodore VIC-20.

The MOS Technology 6567/8562/8564 (NTSC versions) and 6569/8565/8566 (PAL) were accepted as the VIC-II and were acclimated in the Commodore 64.

The MOS Technology 8563/8568 was acclimated in the Commodore 128 to actualize the 80 cavalcade argument mode, calm with the accustomed VIC-II dent for the C64 accordant video modes.

The MOS Technology 7360 Argument Editing Device (TED) was acclimated in the Commodore Plus/4, Commodore 16 and Commodore 116 computers and had an chip audio capability.

The Picture Processing Unit was a video co-processor advised by Ricoh for Nintendo's use in the Famicom and Nintendo Entertainment System. It was affiliated to 2048 bytes of committed video RAM, and had a committed abode bus that accustomed added RAM or ROM to be accessed from the bold cartridge. A scrollable playfield of 256×240 pixels was supported, forth with a affectation account of 64 OBJs (sprites), of which 8 could be displayed per scanline.

The TMS9918 is accepted as the Video Affectation Processor (VDP) and was aboriginal advised for the Texas Instruments TI-99/4, but was after additionally acclimated in systems like the MSX (MSX-1), ColecoVision, Memotech MTX series, and for the Sega SG-1000 and SC-3000.

The NEC µPD7220. Acclimated in some high-end cartoon boards for the IBM PC in the mid 80s, conspicuously in articles from Number 9 Computer Company

Video Coprocessors

The ANTIC (Alpha-Numeric Television Interface Circuit) was an aboriginal video arrangement dent acclimated in the Atari 8-bit ancestors of microcomputers. It could apprehend a "Display list" with its own congenital in CPU and use this abstracts to accomplish a circuitous video signal.

The Yamaha V9938 is an bigger adaptation of the TMS9918, and was mainly acclimated in the MSX2.

The Yamaha V9958 is the Video Display Processor (VDP) mainly acclimated in the MSX 2+ and MSX turbo R computers

Alternatives to using a VDC chip

Note that abounding earlier home-computer did not use a VDP-chip, but congenital the accomplished video affectation ambassador from a lot of detached argumentation chips, (examples are the Apple II, PET, and TRS-80). Because these methods are actual adjustable the video affectation generators could be actual capable, (or acutely primitive, depending of the affection of the design) but additionally bare a lot of components.

Many aboriginal systems acclimated some anatomy of an aboriginal programmable argumentation arrangement to actualize a video system, examples accommodate the ZX Spectrum and ZX-81 systems and Elektronika BK-0010 but there were abounding others. Aboriginal implementations are generally actual primitive, but after implementations could aftereffect in adequately avant-garde video systems like the one in the SAM Coupé.

These systems could appropriately body a actual able arrangement with almost few components, but the low transistor calculation of aboriginal programmable argumentation meant that the capabilities of aboriginal PLA based systems generally were beneath absorbing than those application the video interface controllers or video coprocessors that were accessible at the aforementioned time. After PLA solutions, like those application CPLDs or FPGAs could aftereffect in abundant added avant-garde video systems, before those congenital application off the shelf components.

An generally acclimated amalgam band-aid was to use a video interface ambassador (often the Motorola 6845) as a base and aggrandize its capabilities with programmable argumentation or an ASIC. An archetype of such a amalgam band-aid is the aboriginal VGA card, that acclimated an 6845 in aggregate with an ASIC, that is the acumen why all accepted VGA based video systems still use the accouterments registers that were provided by the 6845