LCD blink line and invert a line

Hi all ! Im new here on this forum with arduino SDK. I was bourning a couple of Mega to start with it.

Now what i want to do it's easy.. i hope... Print text on a 4x20 LCD...but after this, blink a line..not only the cursor the whole line. And the same thing about the line, but now invert the printed line, backgrond turned on and the letter itself turned off. Or some remark at that line..etc.

All this using 6 wires more (DB4-DB7,RS,E).

Best Regards! Frank

As far as I know a character LCD will not allow you to invert the letters. You would need to create custom characters for all of your inverted letters, but there probably won’t be room in CGRAM for all of the custom characters you would need.

You could blink a line, though. Just alternate between printing the line and a string of block characters (255). Note that there will be small gaps between the blocks.

  • Ben

Yes Ben is correct you can't do this on a standard LCD however what does this mean?

I was bourning a couple of Mega to start with it.

I know I am not too young anymore, but I do have sons in their 20s, but I have no idea what this is. :-[

I have no idea about bourning, but I suspect Mega refers to the AtMega family of µC... Was that your question ?

burning i think

As far as I know a character LCD will not allow you to invert the letters. You would need to create custom characters for all of your inverted letters, but there probably won’t be room in CGRAM for all of the custom characters you would need.

  • Ben

Is storing a custom character fast enough that he could keep changing what is stored as long as the total number of different custom characters on the screen wasn’t more than the room in CGRAM? (I think that’s 8 or 16, so for a 20x40 screen, maybe he could get away with it). Especially if only one line or a small portion is inverted.

Thanks all!. :o My idea is create a interface between the user and the device.

For that i was thinking use a selectable list. When the user select one item, this item blink waiting for the confirmation (ACK) from the device, and then the display shows the selected item inverting the text, or marking it in some way.

I do this some time ago with the graphic LCD's.

What i'm thinking do is charge the complete line (20 char) inverted using pixel mode, and then show it. For this i think the LCD must keep in CMD mode?, and then print the text?. I never try to re-write, or charge the non-ASCCI chars on the device char list, can i do this?

Best Regards! Frank

Is storing a custom character fast enough that he could keep changing what is stored as long as the total number of different custom characters on the screen wasn't more than the room in CGRAM? (I think that's 8 or 16, so for a 20x40 screen, maybe he could get away with it). Especially if only one line or a small portion is inverted.

Yes, he could keep changing the custom characters, but as you say, he could never have more than 8 (or possibly 16 if his larger LCD supports it) different custom characters at the screen at any given time, so far as I know.

  • Ben