chain from 3 x 74hc165 shiftin registers

[Black_Parrot]

Anyone? Is there the way to use more then 2 input registers?

[runaway_pancake]

http://dduino.blogspot.com/2012/04/arduino-74hc165-psio-shift-regsiter.html

[graynomad]

I've looked at that code 10 times and I can't see any reason it will work for 2 chips and not for 3. I would however change

Code: [Select]

      bytesVal |= (bitVal << ((DATA_WIDTH-1) - i));

which I think is unnecessarily complex and time-consuming to

Code: [Select]

bytesVal << 1;
bytesVal |= bitVal;
 

I can't see that has anything to do with the problem but code that's difficult to understand is always worth changing.

______
Rob

[runaway_pancake]

http://www.gammon.com.au/forum/?id=11979

[musterstrasse]

Hey Black_Parrot,

I just read your post and see some similarities to my post. Especially the case that two inputs fire the same time happens to me as well.  I do use two SN74HC165N daisy-chained.

Here is my story:
http://forum.arduino.cc/index.php?topic=222209.0

Let me know if you are making progress.
I will keep you posted.

Thanks,
Musterstrasse

[runaway_pancake]

Are we having fun yet?
Anybody need help here?
I worked out a sketch of my own, if anyone is interested - Reply.
(Didn't want to just go and cast pearls before... well, anyway.)

[Grumpy_Mike]

I've looked at that code 10 times and I can't see any reason it will work for 2 chips and not for 3.

I am with Rob, he must have a hardware problem not a code issue.

[Lord_Belenos]

I found this solution to make the example found here  http://playground.arduino.cc/Code/ShiftRegSN74HC165N work with 3 or 4 chips: just change this line

Code: [Select]

byte bitVal;
found in the read_shift_regs() function into this one

Code: [Select]

long bitVal;
and it seems to work fine.
Hope it helps.