ModuleWare Reference Guide - Hornad

Logic PartsGated OR (or1)Gated OR (or1)This part performs a logical OR of each bit of input port din with thescalar input port ena. The result is placed on the output port dout. Thispart allows a single control bit to OR a whole bus.This part is equivalent to n 2-bit OR gates where n is the port width. If thewidth of din = 1, this part is equivalent to the N-Input OR Gate (or) with2 input ports.Functiondout = din0 OR ena (For every bit of the output port dout).Truth TableThis table is for positive polarity. For negative polarity, invert the values.Table 2-19. Gated OR Truth Tabledin(i) ena dout(i)0 0 00 1 11 0 11 1 1ParametersTable 2-20. Gated OR ParametersParameter Values Defaultdin, dout Port widths (must be > 0) Automaticdin_type, ena_type, dout_type ActiveHigh, ActiveLow ActiveHighDesign Rule Checks• An error is issued if the width of any port cannot be determined, port ena does not have afixed width of 1 or if ports din0 and dout are not the same width.• A warning is issued and HDL generation fails for this part if either of ports din and dout arenot connected.46ModuleWare Reference Manual, Library Version 1.9September 18, 2008