These parallel-in or serial-in, serial-out shift registers fea- ture gated clock inputs and an overriding clear input. All inputs are buffered to lower the drive. 74LS Counter Shift Registers are available at Mouser Electronics. Mouser offers inventory, pricing, & datasheets for 74LS Counter Shift Registers. Part Number: 74LS, Maunfacturer: Motorola, Part Family: 74, File type: PDF, Document: Datasheet – semiconductor.
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74HC pinouts (shiftIN)
The most misleading part of this image however is that the blue lead from Arduino GND looks like it goes to PIN 15 on the – it actually goes to the ground rail and PIN 15 is connected to Ard 8, but is hidden. This will allow the system clock to be free running and the register stopped on command with the other clock input.
A buffered direct clear input overrides all other inputs, including the clock, and sets all flip-flops to zero. The LS is a parallel-in or serial-in, serial-out shift register and has a complexity of 77 equivalent datwsheet with gated clock inputs and an overriding clear input.
Clocking is inhibited when either of the clock inputs are held high, holding either input low enables the other clock input.
74LS Datasheet(PDF) – TI store
Maybe I’ve got the input pin pull-down resistors the wrong way round!? For those that follow, the correct pinouts are A change from low-to-high on the clock inhibit input should only be done when the clock input is high.
Don’t know where it came from. That’s exactly what I needed to know. Hence, I ran it all up with the and got on quite well with it.
Synchronous loading occurs 744ls166 the next clock pulse when this is low and the parallel data inputs are enabled. Want to post a buying lead? My friend and I had both ordered some s but during the shipping wait I happily found a in my stash of bits. Yep, I’m getting that. This indicates that the pin should have a zero to activate the name of the function.
This is the way most chips work. Pin 6 is the clock inhibit and should be connected to ground for correct operation.
That is to reset it you need to put it low. I’ve stripped back my code to troubleshoot it. Therefore to take it out of reset you place it high. James’ datasheet link yields a somewhat friendlier datasheet than the one I’d found from TI.
No pin 13 is an output not an input. I had one mysteriously in my box-o-bits Now my order of 74HC chips has arrived I have found datasheft the pinouts are not only different but have different names. The was quite easy I thought but the datasheet has gotten me a little foxed. This is what I have so far We didn’t get time to make the swap back then but the project is back on the table now and we’re both stumped as to why it’s not working.
When high, this input enables the serial data input and couples the eight flip-flops for serial shifting with each clock pulse. Clocking is done on the low-to-high level edge of the clock pulse via a two input positive NOR gate, which permits one input to be used as a clock enable or clock inhibit function.
I have found that TI data sheets are always very thorougher but steeped in their own convention. What else in the data sheet are you having trouble with?
74LS165N, 74LS165PC, 74LS166
The connections to the Arduino are: By utilizing input clamping diodes, switching transients are minimized and system design simplified. Your buying lead can then be posted, and the reliable suppliers will quote via our online message system or other channels soon. Just out of curiosity Capacitor Expert By Day, Enginerd by night.
Dwtasheet first I tried modifying the wiring then I stripped it all out and started over. How long will receive a response. I hope this serves others too. I did have all this working nicely with a chip: I started this thread whilst trying to get my head around the different pin labeling on the Does anyone have a keener eye than me?