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Topic: m74hc595b1 vs 74hc595? (Read 1 time) previous topic - next topic

ironheartbj18

I am wondering m74hc595b1 is same as 74hc595 microprocessor? I cant find what these are difference?


CrossRoads

Both are 8-bit shift registers. No difference - just different manufacturers.
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.


CrossRoads

Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

ironheartbj18

I am reading the book called beginning Arduino on the Chapter 17.
I am seeing the Pin diagram of 595. I am not sure if it that right my answer. I wrote some add from other website.
let said to Pin 12 as the Clock Pin ( SH_CP SRCLK serial clock) , Pin 14 as the Data Pin ( DS Data in), and Pin 11 as the Latch Pin
(ST_ CP RCLK REGISTER CLOCK)

Are those correct statement ?

please help me with that

Thanks you

ironheartbj18

i found more information about shift out
here is http://www.arduino.cc/en/Tutorial/ShiftOut

thanks anyway

ironheartbj18

Hello everybody again! I am focus on 595 experiment without the Arduino.  I want to learn 595 how it works by using the three buttons with LATCH (12 Pin as for RCK) , CLOCK (11 Pin as for SCK) , DATA (14 Pin as for DS).  I was following exactly what the ShiftOut instructor. I noticed when I assembly jumper wires connected on the breadboard everything looking good except the LATCH Pin is very sensitivity once i hooked up with LOW it and the 8 leds OUTPUT 595 started flashing at same time. Even the DATA, CLOCK is LOW. Does anyone know what cause of that?


Grumpy_Mike


i found more information about shift out
here is http://www.arduino.cc/en/Tutorial/ShiftOut

Bad tutorial, that capacitor should not be on the latch pin, you could damage your arduino like that. It needs to be moved to the +ve power pin on the shift register.

Quote
I want to learn 595 how it works by using the three buttons

So how have you wired this up?
You need buttons to ground and pull up resistors on each of the three inputs.

Paul__B


i found more information about shift out
here is http://www.arduino.cc/en/Tutorial/ShiftOut


That tutorial seems to be seriously broken in so many ways.  Just a snippet that caught my eye:
Code: [Select]
//for each bit in the byte myDataOut?
  //NOTICE THAT WE ARE COUNTING DOWN in our for loop
  //This means that %00000001 or "1" will go through such
  //that it will be pin Q0 that lights.
  for (i=7; i>=0; i--)  {
    digitalWrite(myClockPin, 0);


You write "myClockPin" to zero eight (presuming the index is in fact, signed) times in succession without doing anything else?

Why?

And the bit about loading a digital control line with a capacitor - just so wrong!

If it involved buttons, I could anticipate the suggestion of "debouncing" with a capacitor, and I would be advising against that in favour of software debouncing, but having not even gone to the trouble of reviewing the whole tutorial (so no idea what other kludges are there), it just looks too shabby to advise reading at all.

Better to look for some reliable information (well-vetted and responsive to corrections; more than we can say for the Arduino site tutorials, sad to say) on Nick Gammon's pages.

Grumpy_Mike

We have been complaining about that tutorial for years but nothing gets done.

ironheartbj18

I am having a problem with M74HC595B1 by STMicroelectronics. It took me a week to figure it out what wrong with them sometime they do skip OUTPUT when i trying to push two buttons CLOCK and LATCH. They does not in the order OUTPUT.

I did not know that about the Texas instruments is doing better with buttons. The data sheet does not said anything about the buttons.

I have seen Sparkfun is only ONE selling for Texas Instruments.


http://www.youtube.com/watch?v=d8V8SRsJRoI&feature=c4-overview&list=UUrVcEskLufMend7_62_CDpw

Grumpy_Mike

No there is no difference.
You need decoupling on the chip's power supply and debounce on the buttons.

CrossRoads

Digikey sells several brands of 74HC595:
http://www.digikey.com/product-search/en?x=-1305&y=-73&lang=en&site=us&KeyWords=74hc595
None will work properly with power supply decoupling and debouncing the control buttons - specifically the serial clock pin. The others are not critical.
Designing & building electrical circuits for over 25 years. Check out the ATMega1284P based Bobuino and other '328P & '1284P creations & offerings at  www.crossroadsfencing.com/BobuinoRev17.
Arduino for Teens available at Amazon.com.

Grumpy_Mike

Also I can't see any pull up resistors on that circuit the inputs look like they are floating.

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