1bit Hi-Z IN/OUT bidirection I/O

< Function description >

File name
HiZ_bidirect_1bit.nsl
Function
Example code of bidirectional signal with high impedance control.
Explane
Signal description
This code shown bidirectional signal control example.
A bidirection lines are declared as ‘PortA’ and ‘PortB’.

At ‘DIR’ signal is ‘L’ and ‘OEN’ is ‘H’, a value of ‘PortB’ is transfered to ‘PortA’.
At ‘DIR’ signal is ‘H’ and ‘OEN’ is ‘H’, a value of ‘PortA’ is transfered to ‘PortB’.

Also, ‘OEN’ signal is ‘L’, ‘PortA’ and ‘PortB’ signals will be ‘Hi-Z’ status.

TruthTable :

  -----------------------------
  | DIR | OEN | PortA | PortB |
  -----------------------------
  |  L  |  H  |  HiZ  | PortA |
  |  H  |  H  | PortB |  HiZ  |
  |  X  |  L  |  HiZ  |  HiZ  |
  -----------------------------
Note
This function is same an one part of 74245 – TTL standard logic -.