Scaleable refresh display controller
First Claim
1. A wireless communications device for viewing an image on a display, comprising:
- a radio frequency (RF) circuit having an input coupled for receiving a RF input signal and an output;
a demodulator having an input coupled to the output of the RF circuit and having an output for providing a baseband data signal;
a decoder circuit having an input for receiving the baseband data signal for providing image data, where the decoder circuit counts a number of pixels within a line of the image data to produce a pixel count and divides a number of pixels within a line of the display by the pixel count to compute a pixel rate divisor;
a circuit for clocking the display, including(1) a first divider having a clock input for receiving a clock signal, a data input for receiving the pixel rate divisor, and an output for providing a pixel clock for transferring the image data to the display; and
(2) a second divider having a clock input for receiving the pixel clock, a data input for receiving the pixel count, and an output for providing a line clock having a substantially constant period as a period of the pixel clock varies.
20 Assignments
0 Petitions
Accused Products
Abstract
A display controller (112) reduces the power consumed in displaying a graphics image in a portable wireless communications device (100) when a graphics image is smaller than the size of the display (118). The number of rows and columns used to display the graphics image is counted by a decoder (108) which is a microcontroller used to operate the communications device (100). The decoder (108) provides the reduced row or column count to the display controller (112), which reduces the frequencies of clocks (PIXEL CLOCK, LINE PULSE, FRAME PULSE) used for timing data transfers to the display (118). Power is reduced by operating the display (118) at a lower frequency while acceptable frame refresh rates are maintained.
76 Citations
14 Claims
-
1. A wireless communications device for viewing an image on a display, comprising:
-
a radio frequency (RF) circuit having an input coupled for receiving a RF input signal and an output; a demodulator having an input coupled to the output of the RF circuit and having an output for providing a baseband data signal; a decoder circuit having an input for receiving the baseband data signal for providing image data, where the decoder circuit counts a number of pixels within a line of the image data to produce a pixel count and divides a number of pixels within a line of the display by the pixel count to compute a pixel rate divisor; a circuit for clocking the display, including (1) a first divider having a clock input for receiving a clock signal, a data input for receiving the pixel rate divisor, and an output for providing a pixel clock for transferring the image data to the display; and (2) a second divider having a clock input for receiving the pixel clock, a data input for receiving the pixel count, and an output for providing a line clock having a substantially constant period as a period of the pixel clock varies.
-
-
2. A clocking circuit for driving a display device, comprising:
-
a decoder circuit having an input for receiving a data stream and an output for providing image data, the decoder circuit counting a number of pixels within a line of the image data to produce a pixel count and dividing a number of pixels within a line of the display device by the pixel count to compute a pixel rate divisor; a first divider having a clock input for receiving a clock signal, a data input for receiving the pixel rate divisor, and an output for providing a pixel clock for transferring the image data; and a second divider having a clock input for receiving the pixel clock, a data input for receiving the pixel count, and an output for providing a line clock having a substantially constant period as a period of the pixel clock varies. - View Dependent Claims (3, 4, 5, 6, 7, 8, 9)
-
-
10. A method of clocking a display, comprising the steps of:
-
counting a number of pixels within a line of the image data to produce a pixel count; dividing a number of pixels within a line of the display by the pixel count to compute a pixel rate divisor; counting a system clock to the pixel rate divisor to produce a pixel clock for transferring the image data; and counting the pixel clock to the pixel count to produce a line clock having a substantially constant period as a period of the pixel clock varies. - View Dependent Claims (11, 12, 13, 14)
-
Specification