Typo

Thread Starter

gorgondrak

Joined Nov 17, 2014
61
DIGI book chapter 12 Shift Registers part 12.2.1

Serial-in/serial-out devices under the device labeled CD4517b dual 64-bit serial-in/ serial-out shift register

There is no CLB labeled in the graphic, only a CL8.

A CD4517b dual 64-bit shift register is shown above. Note the taps at the 16th, 32nd, and 48th stages. That means that shift registers of those lengths can be configured from one of the 64-bit shifters. Of course, the 64-bit shifters may be cascaded to yield an 80-bit, 96-bit, 112-bit, or 128-bit shift register. The clock CLA and CLB need to be paralleled when cascading the two shifters. WEB and WEB are grounded for normal shifting operations. The data inputs to the shift registers A and B are DA and DB respectively.

Suppose that we require a 16-bit shift register. Can this be configured with the CD4517b? How about a 64-shift register from the same part?






Above we show A CD4517b wired as a 16-bit shift register for section B. The clock for section B is CLB. The data is clocked in at CLB. And the data delayed by 16-clocks is picked of off Q16B. WEB , the write enable, is grounded.
 
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Wendy

Joined Mar 24, 2008
23,415
It would help if you would show the link, as in URL, to the section you are talking about. Have you notice how I do it with quotes and the URL link?
 

Thread Starter

gorgondrak

Joined Nov 17, 2014
61
http://www.allaboutcircuits.com/vol_4/chpt_12/2.html

There is only 1 WEb input and 1 WEa input.
A CD4517b dual 64-bit shift register is shown above. Note the taps at the 16th, 32nd, and 48th stages. That means that shift registers of those lengths can be configured from one of the 64-bit shifters. Of course, the 64-bit shifters may be cascaded to yield an 80-bit, 96-bit, 112-bit, or 128-bit shift register. The clock CLA and CLB need to be paralleled when cascading the two shifters. WEB and WEB are grounded for normal shifting operations. The data inputs to the shift registers A and B are DA and DB respectively.

Suppose that we require a 16-bit shift register. Can this be configured with the CD4517b? How about a 64-shift register from the same part?






Above we show A CD4517b wired as a 16-bit shift register for section B. The clock for section B is CLB. The data is clocked in at CLB. And the data delayed by 16-clocks is picked of off Q16B. WEB , the write enable, is grounded.

Above we also show the same CD4517b wired as a 64-bit shift register for the independent section A. The clock for section A is CLA. The data enters at CLA. The data delayed by 64-clock pulses is picked up from Q64A. WEA, the write enable for section A, is grounded.
 
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Wendy

Joined Mar 24, 2008
23,415
OK, next lesson, we can get the page we want, but counting graphics doesn't work too well, I only count 13.

Use the quote command. It goes between the square brackets []. Since the site software would hide it if I used it direct I'll show it using {} brackets.

{quote} Bill Marsden said this!{/quote}

The slash ends the command. This is the basis for many special script commands in XenForo and many other software forum and text packages.

Pick the area you want to quote and highlight it, including graphics. On my system it will become blue. Then use <CNTL>C or the left click <COPY>to copy it. You must do this with the cursor over text material (graphics material brings up different menu options, which aren't usable).

Paste the copied material between the two quote commands. You will not be able to see the quote commands, but they are there. You can also edit material between the quotes to do things like change color to highlight the questionable text.





A CD4517b dual 64-bit shift register is shown above. Note the taps at the 16th, 32nd, and 48th stages. That means that shift registers of those lengths can be configured from one of the 64-bit shifters. Of course, the 64-bit shifters may be cascaded to yield an 80-bit, 96-bit, 112-bit, or 128-bit shift register. The clock CLA and CLB need to be paralleled when cascading the two shifters. WEB and WEB are grounded for normal shifting operations. The data inputs to the shift registers A and B are DA and DB respectively.

Suppose that we require a 16-bit shift register. Can this be configured with the CD4517b? How about a 64-shift register from the same part?





I'm trying to get you where you can display your points clearly and accurately. You will find this valuable for other applications else where.

As a moderator I can edit your posts. This means I can show you something in a post you've made, and you can use the
button to do see the text as it is truly stored in your post.

I've been doing this more than a few years, and I like teaching. If you are interested I can show you other tricks, but for now I am trying to make it where we can communicate well.
 

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Thread Starter

gorgondrak

Joined Nov 17, 2014
61
Knowing how to highlight the questionable text would be helpful.

http://www.allaboutcircuits.com/vol_4/chpt_12/2.html

DIGI book chapter 12 Shift Registers part 12.2 Serial-in/serial-out shift register

The following data was extracted from the CD4006b data sheet for operation at 5VDC, which serves as an example to illustrate timing.

[*]

tS=100ns
tH=60ns
tP=200-400ns typ/max
tS is the setup time, the time data must be present before clock time. In this case data must be present at D 100ns prior to the clock. Furthermore, the data must be held for hold time tH=60ns after clock time. These two conditions must be met to reliably clock data from D to Q of the Flip-Flop.

There is no problem meeting the setup time of 60ns as the data at D has been there for the whole previous clock period if it comes from another shift register stage. For example, at a clock frequency of 1 Mhz, the clock period is 1000 µs, plenty of time. Data will actually be present for 1000µs prior to the clock, which is much greater than the minimum required tS of 60ns.
The clock period of 1 MHz is 1us or 1000ns. Also, it is abbreviated with a capital H; MHz.
 
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Wendy

Joined Mar 24, 2008
23,415
When you edit a file you get a screen that looks a lot like this. Highlight the characters you want to change and use the logo I have circled in red to change their color. All of this is in what is called BB code.
 

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Thread Starter

gorgondrak

Joined Nov 17, 2014
61
The graphics aren't showing up on my screen and since I am on a tablet it will not let me highlight more than one word at a time in edit mode. It also wouldn't let me highlight the word "is".
 
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