Hi all, Having an issue with my project involving shift registers.
I have 9 registers all chained together, and the first 7 work perfectly, Outputing whatever i send them with shiftOut, but the last two are not working...
They seem to be constantly outputing on all 8 outputs
If i send out '0' on every register, every output turns off, EXCEPT for all of the outputs on the last two registers...
they just wont turn off!
The data pin also seems to have a voltage (BUT ONLY ON THE LAST TWO + THE DATA OUTPUT ON THE 7th)
Well, if the data output of the 7th shift register is stuck HIGH that would explain why every shift stage beyond that sees a HIGH.
Swap the 5th and 7th chips. If the problem follows the chip then the chip is bad. If the problem stays on the 7th chip there is probably a bad connection near there.
Check the connections of the 7th shift register. Could be that a solder connection or trace is bad (open) or bridged to another pin.
If you don't see any problems in the traces and or solder joints it's probably time to de-solder. If you do get that far it might be good to pick up some sockets for whatever chips you remove.