TEA1002
The TEA1002 is a PAL video encoder chip produced by Mullard in 1982 and used on the Mattel Aquarius computer, the AlphaTantel Prestel adapter and the Microvector 256 color graphics display interface for Nascom and Gemini computers.
It was also used on teletext decoders and color bar generators associated with video test equipment.
It generates 16 colors based on Luminance, Chrominance and Saturation, usually with the 8 basic colors being similar to the EBU 75% color bars.
Levels
According to the TEA1002 datasheet, colors are formed by the combination of three signals, roughly equivalent to the HSL colorspace: LuminanceInternally colors are stored in a 4-bit RGBI arrangement. There are three bits for the RGB components and an inverter logic input'' bit that controls a variation of the base color.
The following table lists the internal signals and shows an approximation of the generated colors, as seen on a web standard sRGB monitor. Colors could be different when seen on an analog PAL CRT television.
| Color | R | G | B | INV | Luminance | Chroma | Chroma |
| Black | 0 | 0 | 0 | 0 | 0.0 | - | - |
| Red | 1 | 0 | 0 | 0 | 22.5 | 103 | ±48 |
| Green | 0 | 1 | 0 | 0 | 44.0 | 241 | ±44 |
| Yellow | 1 | 1 | 0 | 0 | 66.5 | 167 | ±33 |
| Blue | 0 | 0 | 1 | 0 | 8.5 | 347 | ±33 |
| Magenta | 1 | 0 | 1 | 0 | 31.0 | 61 | ±44 |
| Cyan | 0 | 1 | 1 | 0 | 52.5 | 283 | ±48 |
| White | 1 | 1 | 1 | 0 | 100.0 | - | - |
| Grey | 0 | 0 | 0 | 1 | 75.0 | - | - |
| Cyan | 1 | 0 | 0 | 1 | 52.5 | 283 | ±24 |
| Magenta | 0 | 1 | 0 | 1 | 31.0 | 61 | ±22 |
| Blue | 1 | 1 | 0 | 1 | 8.5 | 347 | ±17 |
| Yellow | 0 | 0 | 1 | 1 | 66.5 | 167 | ±17 |
| Green | 1 | 0 | 0 | 1 | 44.0 | 241 | ±22 |
| Red | 0 | 1 | 1 | 1 | 22.5 | 103 | ±24 |
| Black | 1 | 1 | 1 | 1 | 0.0 | - | - |
An alternate configuration of the chip allows it to output 95% luminance color bars - similar to BBC colour bars, more suited for usage in teletext decoders.
| Color | R | G | B | INV | Luminance | Chroma | Chroma |
| Black | 0 | 0 | 0 | 0 | 0.0 | - | - |
| Red | 1 | 0 | 0 | 0 | 47.5 | 103 | ±48 |
| Green | 0 | 1 | 0 | 0 | 69 | 241 | ±44 |
| Yellow | 1 | 1 | 0 | 0 | 91.5 | 167 | ±33 |
| Blue | 0 | 0 | 1 | 0 | 33.5 | 347 | ±33 |
| Magenta | 1 | 0 | 0 | 0 | 56 | 61 | ±44 |
| Cyan | 0 | 1 | 1 | 0 | 77.5 | 283 | ±48 |
| White | 1 | 1 | 1 | 0 | 100.0 | - | - |
| Grey | 0 | 0 | 0 | 1 | 100.0 | - | - |
| Cyan | 1 | 0 | 0 | 1 | 77.5 | 283 | ±24 |
| Magenta | 0 | 1 | 0 | 1 | 56 | 61 | ±22 |
| Blue | 1 | 1 | 0 | 1 | 33.5 | 347 | ±17 |
| Yellow | 0 | 0 | 1 | 1 | 91.5 | 167 | ±17 |
| Green | 1 | 0 | 0 | 1 | 69 | 241 | ±22 |
| Red | 0 | 1 | 1 | 1 | 47.5 | 103 | ±24 |
| Black | 1 | 1 | 1 | 1 | 0.0 | - | - |