ModuleWare Reference Guide - Hornad

IntroductionSupported VHDL Packages and TypesSupported VHDL Packages and TypesThe ModuleWare parts support the use of either std_logic_arith or numeric_std with thepackage std_logic_1164.An error is issued during HDL generation if any other package is used.The ModuleWare parts also support signals of types (std_logic, std_logic_vector, std_ulogic,std_ulogic_vector, signed, or unsigned) connected to any of its ports. A warning level one isissued if a signal of a different type other than these is connected to any of the ports.Polarity ControlIn general, polarity control is provided for all control and status ports but not for data portsexcept for all ports on the Logic parts.The polarity for a port is specified by a control parameter. The naming convention for thisparameter is as follows:• If the port is named , the parameter is named _type.• Most of the polarity-control parameters are enumerated with values of ActiveHigh orRising (positive polarity) and ActiveLow or Falling (negative polarity).The polarity of a port is shown by an indicator on the symbol or instance. Thus, if the valueof the parameter is set to ActiveLow, an indicator appears on the port. If the value is set toActiveHigh, the indicator disappears on the port.You are advised not to edit the control parameter of an unconnected port, because this canmodify the default operation. The polarity of the port is implemented in the generated HDLcode.Function_type = ActiveHigh has positive polarity_type = ActiveLow has negative polarity (shown as )Notes• The default value for the control parameter _type is usually ActiveHigh. Pleasesee individual parts for part-specific defaults.• The control parameters of the rst and the clk ports on the Sequential parts have differentenumerated sets of values which are covered in later sections.18ModuleWare Reference Manual, Library Version 1.9September 18, 2008