Abstract: A voltage detection circuit control device includes a first voltage detection circuit which detects a first voltage, a second voltage detection circuit which detects a second voltage higher than the first voltage, and an operation signal generating circuit which is connected to the first and second voltage detection circuits and produces a signal for controlling an operation of the first voltage detection circuit on the basis of a voltage detection signal from the second voltage detection circuit.

Abstract: A voltage detection circuit control device includes a first voltage detection circuit which detects a first voltage, a second voltage detection circuit which detects a second voltage higher than the first voltage, and an operation signal generating circuit which is connected to the first and second voltage detection circuits and produces a signal for controlling an operation of the first voltage detection circuit on the basis of a voltage detection signal from the second voltage detection circuit.

Abstract: A voltage detection circuit control device includes a first voltage detection circuit which detects a first voltage, a second voltage detection circuit which detects a second voltage higher than the first voltage, and an operation signal generating circuit which is connected to the first and second voltage detection circuits and produces a signal for controlling an operation of the first voltage detection circuit on the basis of a voltage detection signal from the second voltage detection circuit.

Abstract: A voltage detection circuit control device includes a first voltage detection circuit which detects a first voltage, a second voltage detection circuit which detects a second voltage higher than the first voltage, and an operation signal generating circuit which is connected to the first and second voltage detection circuits and produces a signal for controlling an operation of the first voltage detection circuit on the basis of a voltage detection signal from the second voltage detection circuit.

Abstract: Depending on whether the display mode specified by a CPU is the graphics mode or the text mode, the access mode of an image memory is switched. In the text mode, a random access is executed in a single read cycle with the timing synchronizing a video clock to alternate the reading of character codes and attributes with the reading of character fonts on a character basis. This makes shorter the time that the image memory is occupied for screen refreshing, thereby making so much longer the drawing time of the CPU. Furthermore, because an entire display controller functions as a video clock synchronizing circuit, the function of synchronizing the circuits is not necessary, which results in simplified control.

Abstract: A display control apparatus comprises a control signal generator for generating various control signals including pixel video data and a display clock signal synchronous to the pixel video data, a flat-panel controller for driving a flat-panel display according to the control signals, a color palette RAM for color-converting the pixel video data supplied from the control signal generator into a digital RGB signal, and a video DAC for converting the digital RGB signal supplied from the color palette RAM into an analog RGB signal in response to the display clock signal supplied from the control signal generator to drive an analog color CRT display.