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I'm trying to display the letter "A" on LM016L (datasheet). I keep switching the E input but I get nothing.

This is my circuit: datasheet

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closed as unclear what you're asking by Marcus Müller, Leon Heller, Autistic, Dmitry Grigoryev, pjc50 Jan 16 '17 at 11:49

Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

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    \$\begingroup\$ So, all we can tell you is that this isn't working. Explain what debugging this far has revealed. You say you switch the "E" input, but that's just "enable". How do you know things should be displayed? What should happen? Does the device at least draw the expected supply current? We'll need more hints at what might be going wrong. Alos, remove the arduino and fpga tags. You refer to neither in your question, and "hey, there's probably clever people looking out for this tag" is a very discouraged reason to use a tag. \$\endgroup\$ – Marcus Müller Jan 15 '17 at 10:50
  • \$\begingroup\$ @MarcusMüller According to the datasheet I linked, the supplies that I have provided should be right. Or I'm getting it wrong. And the data I have specified to D0...D7 should be displayed when E changes. I have been looking this up for a few hours now and haven't found something that points to my mistake. So, I'd really appreciate it if you could suggest something I can try. \$\endgroup\$ – Myla Izaman Jan 15 '17 at 11:58
  • \$\begingroup\$ @MarcusMüller About the tags, this is part of a project that involves FPGA and when I looked LCD up on the internet, almost all the guides I saw involved Arduino. So I figured maybe I need those to get it to work. Forgive me if this is a rookie mistake. \$\endgroup\$ – Myla Izaman Jan 15 '17 at 12:00
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    \$\begingroup\$ "Forgive me if this is a rookie mistake." Yes, it is :-) I've removed the irrelevant tags, as @MarcusMüller asked. The other contents of your project (e.g. FPGA & Arduino) are unrelated to this question. It's a bit like asking a question about car wheels, but using a "petrol" tag because your car has a petrol engine. It just wastes the time of petrol engine experts, but who know nothing about car wheels, who come to read the question because you used a "petrol" tag. See what I mean? :-) Anyway, I've removed those and added the very relevant HD44780 tag - that is what you need to research. \$\endgroup\$ – SamGibson Jan 15 '17 at 13:19
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I'm trying to display the letter "A" on LM016L. I keep switching the E input but I get nothing.

Your current plan will not work.

Although your linked LCD module datasheet appears to be an abbreviated version, it says this LCD module uses the HD44780 controller. That is what you need to research.

For example, although not all LCD modules which claim to use HD44780 commands behave exactly the same, they tend to start in a "display off" state, and need to be sent the correct commands before they will even start to show anything. Therefore you need to research HD44780 initialisation.

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    \$\begingroup\$ @MylaIzaman, I have deleted my answer (which recommended improving 'E' signal quality) as I belatedly realised that the LCD needs initialising. My answer was rubbish and SamGibson is absolutely right so apologies for wasting your time. \$\endgroup\$ – TonyM Jan 15 '17 at 14:31

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