Quad 7-Segment Display EB008

* Click EB008-30-1 for a datasheet. * The male D-type connectors fit into the Female connectors of 2 of the ports of an upstream board. * A 7-segment display is actually no more than: ** 7 LEDs with long shaped segments, placed in an '8' shape. ** 1 LED to indicate a decimal point. * 7-segment displays can be: ** Common Cathode: where the Cathode of all of the LED's is common and the LEDs are lit by applying a positive voltage to the anode of the specific segment. ** Common Anode: where the Anode of all of the LEDs is common and the LEDs are lit by applying a negative voltage to the cathode of the specific segment. ** The Displays used on the EB008 E-block are of the Common Anode type. * The tricky bit is that we do not have enough pins to drive all these LEDs (8 x 4 = 32 separate LEDs) by our controller. We will solve this by: ** Using the speed of the PICmicro. ** By driving pin 1-2-3 or 4 of J2 we determine which of the four 7-segment displays is active to receive data. ** Data is sent to the active display by the 8 data pins on J1. ** LEDs will emit light for a short time they have been turned off. ** So the trick is that you alternately activate each of the four 7 segment displays in turn, by making the appropriate anode via J2 high, and then send the data to each display by making the appropriate cathodes via J1 low * If you only need one 7-segment display, then this can be activated permanently by putting a jumper next to the screw terminal on the board. This way only J1 is used to drive the left display and no multiplexing is needed. (:nl:)(:table style="clear:both":)