ModuleWare Reference Guide - Hornad

Sequential PartsModulo Counter (modcntr)else at every enabled clk trigger (rising edge if clk_type = Rising, falling edge if clk_type =Falling):creg = 2 n - count + 1= creg + 1dout = (creg = 0)= NOT(creg = 0)if creg = 0 and mode = moduloOtherwiseif dout_type = ActiveHighif dout_type = ActiveLowTruth TablecregnewmsbreloadvalresetvalThe internal registerThe new value of the MSB that is calculated from the current registerstate (by using a LFSR polynomial for count ≥ 6; the NOT of the LSBfor count < 6)The value assigned to registers when all registers contain zero (formodulo mode only)The value assigned to registers on resetThe following tables are for positive polarities. For negative polarities, invert the values.The following truth table is for the output port dout and applies to all counter styles.Table 8-24. Modulo Counter Truth Table — Output Port dout, All Stylescreg (n)dout (n)0 1≠0 0For LFSR counterThis table is for synchronous high reset.Table 8-25. Modulo Counter Truth Table — LFSR Counter, Synchronous HighResetmode clk_en clk rst creg (n-1) creg (n)- 0 - - - creg(n-1)- 1 - 1 - resetvalModulo 1 posedge 0 0 reloadvalWait-for 1 posedge 0 0 {newmsb, creg(n-1)} >> 1- 1 posedge 0 ≠ 0 {newmsb, creg(n-1)} >> 1192ModuleWare Reference Manual, Library Version 1.9September 18, 2008