Abstract: The present invention provides a low cost animation sequence function for OSDs. An animation sequence is produced by changing the attributes associated with a character within the OSD rather than by substituting the character itself. A character may have several different attributes associated with it. These attributes change the colors associated with the pixels within the character producing a different character visually. The attributes are selected and changed according to a predetermined interval to produce the animation sequence. Each attribute is displayed for the predetermined time before moving on to displaying the character using the next attribute to produce the animation sequence. Each color attribute associated with the character in the animation sequence uses up only two words of ROM space, whereas the character itself takes up eight words or more of ROM space. Therefore, there is considerable savings in ROM space as compared to storing a separate character for each animation frame.

Abstract: The present invention provides a low cost OSD system with minimal ROM requirements, minimal computing power required from the microcontroller, and minimal I/O port requirements. The OSD system creates a fixed frame around a small set of programmable characters. The small set of programmable characters is used to create an icon within the OSD display. The icon is selected by sending minimal information to the microcontroller. In one particular example, four bits of information are sent to the microcontroller to select one of the available sixteen different icons. The OSD frame characters and OSD programmable area icon characters are stored in ROM and no RAM is used. The OSD silicon die size is reduced as compared to a traditional OSD silicon die size.

Abstract: A circuit has been shown to illustrate how a vertical indicator can be generated in logic for a simplified OSD generator. The vertical visual indicator generated uses little microcontroller firmware overhead allowing a less powerful microcontroller to be used in the specific application, thus lowering system cost. A single byte is written to a counter to indicate the position of the vertical indicator. The OSD video coming from the OSD logic is overridden with a pixel overwrite signal when the location of the vertical indicator is located. The pixels overwrite whatever is located below the position of the vertical indicator. The pixel overwrite occurs for a predetermined time to fill a predetermined number of pixels. For example, if the vertical indicator is three pixels wide then the pixel overwrite signal occurs until three pixels have been overwritten.

Abstract: A method and apparatus is directed to reducing jitter of the position of an On Screen Display (OSD) associated with a display device. Multiple horizontal signals are produced in response to a vertical flyback signal and a horizontal flyback signal for the display device. Each of the multiple horizontal signals has a different phase. One of the multiple horizontal signals is selected such that its rising edge of the selected horizontal signal occurs at a separate time when compared to the rising edge of the vertical flyback signal. By ensuring that the rising edge of the selected horizontal signal is not coincident with the vertical flyback signal, jitter is minimized in the position of the OSD.

Abstract: The present invention provides a bar indicator that minimizes the burden placed on the microcontroller. A horizontal bar indicator is generated that requires very little microcontroller firmware overhead, allowing a less powerful microcontroller to be used in the application. The reduced firmware requirement translates into smaller microcontroller firmware ROM requirements, thus enabling a lower cost system to be realized. The bar indicator uses a single byte written to a counter to represent the size of the bar. This byte written to the counter is readily available from the actual parameter value representing the size of the bar without significant additional calculation. The OSD video coming from the OSD logic is overridden with a pixel overwrite when the location of the bar indicator is located. The bar overwrites whatever is located at the position of the bar indicator. The pixel override occurs for a predetermined time.

Abstract: Vertical rate deflection signals are generated using a combination of digital and analog techniques. A signal is generated by a switched capacitor type accumulator circuit, a wave shape control circuit, and a DC signal centering circuit. The signal is periodically reset by initializing a first storage circuit in the accumulator circuit to an initial start voltage. A buffer couples the first storage circuit to a first signal output. A second signal output is produced by generating a controlled offset from the first signal output. The second signal output is sampled by a second storage circuit, and subsequently coupled to the first storage circuit. The amplitude and slope of the signal are determined by the controlled offset level. The wave shape control circuit dynamically controls the offset level. By varying the offset level, the waveform shape is adjusted to provide a linear ramp, S corrected ramp, EWPCC parabolic signal or the like.

Abstract: A multiplexed video amplifier circuit includes a video preamplifier and a bias/brightness circuit the output of both being coupled to a switch. The video preamplifier provides a video signal, the bias/brightness circuit provides a DC bias signal, and the switch selectively couples to the output of either the video preamplifier or the bias/brightness circuit. In this way, the switch alternately receives the video signal and the DC bias signal and combines them to provide a single multiplexed video signal with both video and DC bias signal data. This multiplexed video signal is sent to a clamp amplifier and a video amplifier, both of which compare the magnitude of the multiplexed video signal with a reference signal. When the magnitude of the multiplexed video signal transcends the reference signal in a first direction, for example is lower than the reference signal, the clamp amplifier provides the DC bias signal to an external circuit.