Hi again,
In addition to the inconsistancies Mike has asked for clarifications on...
I knew that I can stack more 595, but it'll need me to do Shiftout more then once.
If you have a concern for how many times shiftout() is called, in the configuration you propose you'll actually be calling shiftout() up to 8 times more than with a 595 cascaded alternative. This is because for each individual pin you update you're setting the addresses in parallel on all of the 4051's but only enabling one for output, so you'll need to send that 595 a different bit pattern to update each pin on each 4051. In contrast, with 3x cascaded 595s, you would need to output just 3 bytes via only 3 calls to shiftout() rather than the 24 needed to do the same in your proposed configuration.
binooetomo:
- I dont use 4051 to 'read'.
- I just want more digital output.
Based on this, multiple 595 is ideal. Keeping in mind the questions Mike has raised above.
Cheers ! Geoff