The Color Graphics Adapter (CGA), originally also called the Color/Graphics Adapter or IBM Color/Graphics Monitor Adapter, [1] introduced in 1981, was IBM's first color graphics card for …

The CGA can display 16 colors on a TTL or "Direct Drive" RGBI monitor. However, it can only display all of them at one time in text modes. The colors are encoded as 4-bit binary values, …

Oct 18, 2017 · Unlike an MDA, the CGA card does not contain a clock crystal. Instead, the Oscillator signal on the ISA bus is used to generate timing. This is 14.318MHz (4 times the …

Color Graphics Adapter (CGA) The CGA, released by IBM, supports 4 colours in graphics mode and 8 in text mode at a pixel addressability of 640x200. The CGA provides a vertical refresh of …

The wait state algorithm for the original IBM CGA is basically "wait 1 hchar, then wait for the next lchar, then wait for the next ccycle". That works out at between 3 and 8 ccycles depending on …

Mar 1, 2016 · The CGA card gets its clock timings from the ISA bus, so it runs off the same 14.32 MHz base crystal as the motherboard (standard NTSC frequency generators). This means it is …

May 18, 2018 · Many early PC games demand an 8088 CPU running at 4.77mhz and a true CGA card to display properly. Games such as Striker, Demon Attack and early Ultima titles among …

In the 40 column and graphics modes, the CGA properly interleaves CRTC and CPU accesses, but in the 80 column mode it lacks the bandwidth to seamlessly separate the two types of …

Jun 22, 2012 · As I recently repaired a 5160 motherboard, I was thinking of building an IBM CGA adapter (I'm perfectly aware of Sergey's SVGA card, I've actually built a few of those, but I …

As part of my project to emulate an IBM PC or XT with cycle accuracy, I need to be able to get the machine into a completely known and consistent state, which I call lockstep. That way I can …