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VIDC20
The VIDC20 was a video display controller chip created as an accompanying chip to the ARM CPU as used in RiscPC computer systems. A simpler version of the VIDC20, the VIDC1, was used in the earlier Acorn Archimedes Acorn Archimedes is a family of personal computers designed by Acorn Computers of Cambridge, England. The systems are based on Acorn's own ARM architecture processors and the proprietary operating systems Arthur and RISC OS. The first mode ... computers. A VIDC20 chip controls both the computer's video and sound. The data is read from the 64-bit ARM data bus using DMA control and then processed and converted into the necessary analogue signals to drive the video output displays and sound system. The VIDC20 can handle many more display and sound formats than the original VIDC1 chip found in the Archimedes hardware. It can also read data from VRAM if installed in the machine, otherwise it reads from DRAM. Video Data from the video buffer is converted and proces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acorn Archimedes
Acorn Archimedes is a family of personal computers designed by Acorn Computers of Cambridge, Cambridge, England. The systems are based on Acorn's own ARM architecture processors and the proprietary operating systems Arthur and RISC OS. The first models were introduced in 1987, and systems in the Archimedes family were sold until the mid-1990s. ARM's Reduced instruction set computer, RISC design, a 32-bit CPU (using 26-bit addressing), running at 8 Hertz, MHz, was stated as achieving 4.5+ Million instructions per second, MIPS, which provided a significant upgrade from 8-bit home computers, such as Acorn's previous machines. Claims of being the fastest micro in the world and running at 18 MIPS were also made during tests. Two of the first models—the A305 and A310—were given the BBC branding, with BBC Worldwide, BBC Enterprises regarding the machines as "a continuing part of the original computer literacy project". Dissatisfaction with the branding arrangement was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
VIDC1
The VIDC1 was a Video Display Controller chip created as an accompanying chip to the ARM CPU used in Acorn Archimedes computer systems. Its successor, the VIDC20, was later used in RiscPCs. Video The VIDC1 offers colour depths of 1, 2, 4 or eight bits per colour, allowing for 2, 4, 16 and 256 colour displays (the VIDC20 can offer up to approximately 16 million colours). A colour lookup table or palette register set of 16 12-bit words was provided, offering a range of 4096 colours for each of the colours in those displays or modes employing up to 16 colours. The 12 bits were split in three 4-bit RGB values, with a 4-bit high speed D/A converter for each of the three primary colours. However, in 256 colour modes, 4 bits of the colour data were hardware derived and could not be adjusted. The net result was 256 colours, covering a range of the 4096 available colours. Since the device had no horizontal sync interrupt, it was difficult to display additional colours by changing the pal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RiscPC
The Risc PC is Acorn Computers's RISC OS/ Acorn RISC Machine computer, launched on 15 April 1994, which superseded the Acorn Archimedes. The Acorn PC card and software allows PC compatible software to be run. Like the Archimedes, the Risc PC continues the practice of having the RISC OS operating system in a ROM module. Risc PC augments the ROM-based core OS with a disk-based directory structure containing configuration information, and some applications which had previously been kept in ROM. At the 1996 BETT Educational Computing & Technology Awards, the machine was awarded Gold in the hardware category. Technical specifications Use The Risc PC was used by music composers and scorewriters to run the Sibelius scorewriting software. Between 1994 and 2008, the Risc PC and A7000+ were used in television for broadcast automation, programmed by the UK company OmniBus Systems: once considered "the world leader in television station automation" and at one point automating " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Video Display Controller
A video display controller or VDC (also called a display engine or display interface) 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. Some VDCs also generate an audio signal, but that is not their main function. VDCs were used in the home computers of the 1980s and also in some early video picture systems. The VDC is the main component of the video signal generator logic, responsible for generating the timing of video signals such as the horizontal and vertical synchronization signals and the blanking interval signal. Sometimes other supporting chips were necessary to build a complete system, such as RAM to hold pixel data, ROM to hold character fonts, or some discrete logic such as shift registers. Most often the VDC chip is completely integrated in the logic of the main computer system, (its video RAM appears in the memory map of the main CPU), bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ARM Architecture
ARM (stylised in lowercase as arm, formerly an acronym for Advanced RISC Machines and originally Acorn RISC Machine) is a family of reduced instruction set computer (RISC) instruction set architectures for computer processors, configured for various environments. Arm Ltd. develops the architectures and licenses them to other companies, who design their own products that implement one or more of those architectures, including system on a chip (SoC) and system on module (SOM) designs, that incorporate different components such as memory, interfaces, and radios. It also designs cores that implement these instruction set architectures and licenses these designs to many companies that incorporate those core designs into their own products. There have been several generations of the ARM design. The original ARM1 used a 32-bit internal structure but had a 26-bit address space that limited it to 64 MB of main memory. This limitation was removed in the ARMv3 series, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital-to-analog Converter
In electronics, a digital-to-analog converter (DAC, D/A, D2A, or D-to-A) is a system that converts a digital signal into an analog signal. An analog-to-digital converter (ADC) performs the reverse function. There are several DAC architectures; the suitability of a DAC for a particular application is determined by figures of merit including: resolution, maximum sampling frequency and others. Digital-to-analog conversion can degrade a signal, so a DAC should be specified that has insignificant errors in terms of the application. DACs are commonly used in music players to convert digital data streams into analog audio signals. They are also used in televisions and mobile phones to convert digital video data into analog video signals. These two applications use DACs at opposite ends of the frequency/resolution trade-off. The audio DAC is a low-frequency, high-resolution type while the video DAC is a high-frequency low- to medium-resolution type. Due to the complexity a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graphics Chips
A video display controller or VDC (also called a display engine or display interface) 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. Some VDCs also generate an audio signal, but that is not their main function. VDCs were used in the home computers of the 1980s and also in some early video picture systems. The VDC is the main component of the video signal generator logic, responsible for generating the timing of video signals such as the horizontal and vertical synchronization signals and the blanking interval signal. Sometimes other supporting chips were necessary to build a complete system, such as RAM to hold pixel data, ROM to hold character fonts, or some discrete logic such as shift registers. Most often the VDC chip is completely integrated in the logic of the main computer system, (its video RAM appears in the memory map of the main CPU) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acorn Computers
Acorn Computers Ltd. was a British computer company established in Cambridge, England, in 1978. The company produced a number of computers which were especially popular in the United Kingdom, UK, including the Acorn Electron and the Acorn Archimedes. Acorn's computer dominated the UK educational computer market during the 1980s. Though the company was acquired and largely dismantled in early 1999, with various activities being dispersed amongst new and established companies, its legacy includes the development of reduced instruction set computing (RISC) personal computers. One of its operating systems, , continues to be developed by RISC OS Open. Some activities established by Acorn lived on: technology developed by Arm (company), Arm, created by Acorn as a joint venture with Apple, Inc., Apple and VLSI Technology, VLSI in 1990, is dominant in the mobile phone and personal digital assistant (PDA) microprocessor market. Acorn is sometimes referred to as the "British Apple" and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
