![]() Note that six of the colors are identical to the colors available in High-Resolution (Hi-Res) mode. There are 16 colors available for use in this mode (actually 15 in most cases, since the two shades of gray are identical in brightness on original Apple hardware, except on the Apple II GS). The default for this was 40×40 graphics with text. Thus two pixels, vertically stacked, would fill the screen real estate corresponding to one character in text mode. This mode could display either 40 rows of pixels with four lines of text at the bottom of the screen, or 48 rows of pixels with no text. The blocky, but fast and colorful Lo-Res graphics mode (often known as GR after the BASIC command) was 40 pixels wide, corresponding to the 40 columns on the normal Apple II text screen. Note that some of the AppleWin emulator colors seen here differ markedly from those shown on original hardware. Colors 5 and 10 (gray) are indistinguishable on original hardware however, some emulators (such as older AppleWin versions) display them as different shades. Low-resolution colors 0 (black), 3 (purple), 6 (medium blue), 9 (orange), 12 (light green) and 15 (white) were also available in high-resolution mode. Graphics mode details Color on the Apple II ![]() Some other cards simply added 80-column and lowercase display capabilities, while others allowed output to an IBM CGA monitor through a DE9 output jack. There were PAL color cards which enabled color output on early PAL machines. Numerous add-on video display cards were available for the Apple II series, such as the Apple 80-Column Text Card. In the II GS it was an output for an analog RGB monitor specially designed for the II GS. In the IIc and IIc Plus, this connector was a special-purpose video connector for adapters to digital RGB monitors and RF modulators. In addition to the composite video output jack, the IIc, IIc Plus, and the II GS featured a two-row, 15-pin output. (The exception was the Extended Back version of the Bell & Howell branded black II Plus, which did provide proper video sync, as well as other media oriented features.) However the quality of this output was unreliable the sync signalling was close enough for monitors-which are fairly forgiving-but did not conform closely enough to standards to be suitable for broadcast applications, or even input to a video recorder, without intervening processing. This enabled the computer to be connected to any composite video monitor conforming to the same standard for which the machine was configured. Then, to go back to mixed graphics and text, one would access 0xC053 (49235).Īll Apple II machines featured an RCA jack providing a rough NTSC, PAL, or SECAM composite video output (on non-NTSC machines before the Apple IIe this output is black-and-white only). For example, one could switch from mixed graphics and text to an all-graphics display by accessing location 0xC052 (49234). This allowed the user to do many different things including displaying the graphics screen (any type) without erasing it, displaying the text screen, clearing the last key pressed, or accessing different memory banks. The value read or written does not matter, what counts is the access itself. Reading a value from, or writing any value to, certain memory addresses controlled so called " soft switches". While these occur in all graphics modes, they play a crucial role in Hi-Resolution or Hi-Res mode (see below). Apple's text and graphics modes are based on two different interleave factors of 8:1 and 64:1.Ī second peculiarity of Apple II graphics-the so-called "color fringes"-is yet another by-product of Wozniak's design. ![]() Many home computer systems of the time (as well as today's PC-compatible machines) had an architecture which assigned consecutive blocks of memory to non-consecutive rows on the screen in graphic modes, i.e., interleaving. One notable peculiarity of these modes is a direct result of Apple founder Steve Wozniak's chip-saving design. The graphic modes of the Apple II series were peculiar even by the standards of the late 1970s and early 1980s. 3.4.2.1 Applications using Double High-Resolution.3.4 Graphic modes on later models (IIe, IIc, IIc Plus, IIGS).3.2.2.1 "Alternate Display Mode" on the Apple IIGS.3.2.2 Screen 2 Low-Resolution graphics and text.
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