Thank you Eric,
Your support is great! I really appreciate it.
My test circuit works as I hope. Unfortunately, after all, I realize that the decoder may not the right thing as I hope. When I said outputs I mean we can set whatever combination of values. But here, with the decoder (whatever type) only the 'selected' pin is 'set' which mean only one pin can be effected. For example: if I have a 3-to-8 decoder, I can not set the output (let's say: from pin 0 to pin 7) to: HHLHLLHL (H: High, L: Low), so it is not the same as parallel pins which has this capability!!
I really do not know any method that could help me to do this ?? The parallel port is good, I can set what ever group of bits to the output. The only limittation is the number of pins (8 pins) but I need about more than a hundred.
All the method I know to expand the output, until now, is only help me to set one 'selected pin' not ANY group of pins.
Do you know any solution ?