Design Flow: HW vs. SW Yilin Huang

Overview Software: features and flexibility Hardware: performance Designs have different focuses

SW design flow in V Model Requirements: what to do Specification: how to do Refinement

SW design flow in V Model System design: sub-systems, interfaces Component design: internal structure Refinement

SW design design for change design to ease extensibility  presently needed  expected or possible extensions

HW design flow Constrains  timing, size, power

HW design flow Specification  function and behavior detail Hardware Description  behavior modeling

HW design flow Synthesis  description → components  mapping to target technology (library)

HW design flow Partition, Place and Route  target technology device  library elements → chip

Key differences in HW/SW design Design orientationfeatures, extensibilitytask specific (performance) SoftwareHardware Design processrefinementtransition Design step bound close tospecificationimplementation Requirement of correctnessrelative lowrelative high Timing testabilitydirectly testable synthesizable real timing after PPR Costrelative lowrelative high

Tool costs Software design tools  UML tools 0~$  compilers interpreters also free available Hardware design tools  Commercial mostly $ per seat or from vendors  For Academic Institutes and Research Labs e.g. EUROPRACTICE membership software_price.htmlsoftware_price.html  Some free tools e.g. GHDL(vhdl simulator). Icarus Verilog (simulator and synthesizer), See: gEDA

-END-