Abstract: IC 5 for exclusive use in wiring control has been used in conventional emtion system which is difficult in coping with various types of logic verification and results in high cost. An emulation system according to the invention comprises: a digital input terminal section 8 to which a digital signal is inputted; a plurality of field programmable gate arrays 1 to 4 for verifying logic of the inputted signal; a digital output terminal section 9 for outputting a signal of which logic has been verified; a wiring control selector section 7 which is connected to the digital input terminal section 8 and to the digital output terminal section 9; and an analog universal region 6 which is connected to said wiring control selector section 7; thereby carrying out wiring control between the wiring control selector section and the plurality of field programmable gate arrays, and wiring control among the plurality of field programmable gate arrays.

Abstract: In a digital chrominance signal demodulating device receiving a carrier chrominance signal obtained by digitizing an analog composite video signal, a frequency component near the horizontal frequency of the color subcarrier is extracted, and color-difference signals are output. An identifying circuit forms a selection signal for identifying one of the color-difference signals contained in the carrier chrominance signal, within a color burst signal period, on the basis of a system clock and a horizontal sync signal. A selecting circuit selects the color-difference signals on the basis of the selection signal. The color-difference signals obtained by sampling in accordance with the system clock are kept in phase with the color burst signal. Accordingly, the digital chrominance signal can be demodulated by the use of less expensive digital circuits.