Ega To Vga Converter Circuit
Thanks and good point ! the manual for it does list: CGA/EGA input signal auto scan (15K, 24K, 31KHz), but does not mention TTL. It does tell you how to connect a 9pin CGA/EGA cable to the inputs.... might have to call/email to see if really supports old school TTL EGA input. So is the 8219 also just an upgraded arcade scaler too ? It's manual does not list TTL either. I can build a TTL to analog converter as long as the box does double the H sync for VGA out.
Ega To Vga Converter Circuit
In case you are using the monitor for PCs and you don't need to explore some undocumented features of CGA/EGA cards I do recommend you to use an industry standard for decades VGA card(s) instead of a converter. The image is better than that of CGA or external converters. The refresh/response is natural and does not pass secondary (out of clock) digital processing of converters. These converters are valuable when non-standard (non PC) computers/consoles. A VGA is native and much cheaper option designed by IBM and enhanced by many 3rd party engineering companies and produced and used in hundreds of millions pcs until present time. The converters are hobbyists' projects...
Many vintage computers come with MDA/CGA/EGA boards already installed, and 8-bit friendly VGA cards can be expensive or hard to find. Sometimes it is in your best interest to just get a cheap converter until you can make sure everything else in the machine works before trying to shoehorn a much later video card into an old machine.
Many vintage computers come with MDA/CGA/EGA boards already installed, and 8-bit friendly VGA cards can be expensive or hard to find. Sometimes it is in your best interest to just get a cheap converter until you can make sure everything else in the machine works before trying to shoehorn a much later video card into an old machine..
Thanks everyone ! I think the MCE2VGA may be my best alternative. Testing some older non-VGA stuff is going to be a problem very soon for me and need a simple easy to move around fix. One of the many cards I need to test is an old 1986 era GRX Legacy II which I can find no real good doc's on and prefer not to gamble on trying diff monitors on. Any other suggestions for a cga/mda/ega to vga converter gladly accepted.
Looking for a way to upgrade your old arcade game to a newer monitor? This converter will allow you to take a wide variety of inputs and convert them into a VGA signal that can be connected with a computer monitor cable. There is a built in on screen menu that allows for repositioning, resizing, and other adjusting aspects of picture quality. All boards come with 2 pin power harness and a video input harness (see connection points in main picture)
CGA/EGA/VGA/YUV Component Signal Input as shown in picture above. 640 x 480, 800 x 600, 1024 x 768, 1360 x 768 VGA outputAuto scan for input signals on CGA/EGA/VGA or YUVOn Screen Display with image position control & image zoom control. True digital 24-bit A/D converter for true 16.7 million color conversion, connects to any VGA device. See the detailed instructions in the download section
A CGA (technical acroynm that describes a CRT monitor's video processing format) to VGA (technical acroynm that describes an LCD monitor's video processing format) converter is required to enable the classic game board to communicate correctly with an LCD monitor.
Since it is not a good idea to tap power from the circuit board (and because it likely would not generate the minimum 2 amps to power the converter, anyway), you will have to install an arcade switching power supply to power the converter.
In the Ms. Pac-Man cabinet, finding a place to tap for VAC is not easy, either. You will need to find a suitable tap located on the output side of the line fuse, and in an on-off switch operated circuit.
You will need to replace the original connector with the new one pictured at the bottom of the photo. The new one is not provided with the converter, but it is standard with a new JAMMA wiring harness. This connector is sometimes also called the RGB video cable.
Splice the original connector wires, leading from the game's circuit board, to the new connector in the same order as they appear in the photo. Be sure to splice the wires in their same top to bottom order, not by trying to match wire colors. The top wire of one connector will splice to the top wire of the other connector, and so on.
There is a cluster of four small black buttons (keys) that can be used for certain adjustments. They are marked Up (top button), Down/Auto (bottom button), SW (left button), and Menu (right button) on the converter.
The converter offers a wide range of video signal conversion possibilities. Certainly many more than the one application addressed in this article. But, since there is no manufacturer's operating manual, I cannot offer any help with its other applications.
CEV2TV is the acronym of CGA (Color Graphics Adapter), EGA (Enhanced Graphics Adapter), VGA (Video Graphics Array) to Television set. As the name evokes, CEV2TV is a video converter with significant features.
Unlike the majority of converters on the market, CEV2TV does not alter the original video signals and it does not change the scan frequency signals using scan converters or video scalers. Scan converters and also video scalers alter video frequency and resolution reducing video quality. In CEV2TV the entire process occurs in analog domain. There are not Analog to Digital Converters (ADC), that ensure maximum video quality and native resolution of video.
Only few very expensive video converters are able to display correctly the brown and the dark grey. CEV2TV converts the digital signals to analog with a dedicated Digital to Analog Converter (DAC) that can perfectly produce the entire palette of CGA and EGA: the brow is brown and the dark grey is dark grey.
This GBS-8220 CGA/EGA/YUV to VGA Arcade HD-Converter PCB allows all types of RGB, EGA, VGA or YUV component signals to be up-converter and display on a 31KHz PC VGA monitor, TFT monitor, LCD display, or HD-TV with VGA connection. No need to set dip switches in order to figure out the specific input frequency as all inputs are detected automatically! A great alternative to purchasing a expensive, heavy CGA monitor. Use this converter with an existing computer monitor or install a lightweight LCD display or even use to build your own supergun!
Although IBM's own color display was not available, customers could either use the composite output (with an RF modulator if needed), or the direct-drive output with available third-party monitors that supported the RGBI format and scan rate. Some third-party displays lacked the intensity input, reducing the number of available colors to eight, and many also lacked IBM's unique circuitry which rendered the dark-yellow color as brown, so any software which used brown would be displayed incorrectly.
Color 6 is treated differently; when using the formula above, color 6 would become dark yellow, as seen to the left, but in order to achieve a more pleasing brown tone, special circuitry in most RGBI monitors, starting with the IBM 5153 color display, makes an exception for color 6 and changes its hue from dark yellow to brown by reducing the analogue green signal's amplitude. The exact amount of reduction differed between monitor models: the original IBM 5153 Personal Computer Color Display reduces the green signal's amplitude by about one third, while the IBM 5154 Enhanced Color Display internally converts all 4-bit RGBI color numbers to 6-bit ECD color numbers, which amounts to halving the green signal's amplitude. The Tandy CM-2, CM-4 and CM-11 monitors provide a potentiometer labelled "BROWN ADJ." to adjust the amount of green signal reduction.
For the composite output, these four-bit color numbers are encoded by the CGA's onboard hardware into an NTSC-compatible signal fed to the card's RCA output jack. For cost reasons, this is not done using an RGB-to-YIQ converter as called for by the NTSC standard, but by a series of flip-flops and delay lines.
The relative luminances of the colors produced by the composite color-generating circuit differ between CGA revisions: they are identical for colors 1-6 and 9-14 with early CGAs produced until 1983, and are different for later CGAs due to the addition of additional resistors.