DEF NOT
  PORT IN A
  PORT OUT Z
  INST NAND1 NAND A A Z
  INST OUTZ IO_OUT Z
ENDDEF

DEF AND
  PORT IN A
  PORT IN B
  PORT OUT Z
  INST NAND1 NAND A B Z
  INST NOT1 NOT Z Z
  INST OUTZ IO_OUT Z
ENDDEF

DEF OR
  PORT IN A
  PORT IN B
  PORT OUT Z
  INST NOT1 NOT A A
  INST NOT2 NOT B B
  INST NAND1 NAND A B Z
ENDDEF

DEF TOP
  NET A
  NET B
  NET Z
  INST OR1 OR A B Z
  INST TEST OR_TEST A B Z
  INST OUTA IO_OUT A
  INST OUTB IO_OUT B
  INST OUTZ IO_OUT Z
ENDDEF