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Noise-Generator

LCD Trouble..

8 posts in this topic

Hello everybody,

I already made a Thread in the SID section but I came a bit closer and did see that this section is better.

Core V3 with Pic X685 Midi with MIOS Studio works

MIOS 1.9 uploaded, done

LCD 1602A (HD441) tested with Arduino UNO, works, perfect

Works also with Core, but no Letters, just blocks

Trimmed Luma and Contr, just blocks...

I think I read everything about using the LCD and it should show at minimum "something with letters" :)

By default the HD441 LCD should be supported or do I just did not read and know something which would open me the magic door to see some letters on my LCD, finally?
 

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Hi,
Check your contrast circuit if you have blocks with contrast at minimum too.
Check the pinout and interconnection.
Show us pictures it can help us...

Best

 

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TY. 

i did make pictures but I wasn't sure if they are helpful because of chaotic wiring. 

but, here they are.

1C5D631A-0387-42CB-A7E0-C70042556F80.jpeg

5058D29B-203F-42C3-BABB-947273546CDD.jpeg

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The 4bit interconnection seems fine.
Did you check continuity of all the lines and short-circuit between the lines?
Here a test program to troubleshoot LCD interconnection, it may help you.
...

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Yes, I know that and read the readme but it confuses me a little bit and the better way for me was to get closer with LCDs with another method. It makes me kind of mad to understand what is wrong here, because I have another working Core and the LCD behaves also strange.

Also, few other PICs

And I have an 20268 LCD which Backlight is too weak, what I don't understand because it seems to need more than 5v. If I use it with the Arduino, you don't see enough.

I will protocol next steps with more details, next time I make some tests.

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Just to be sure:
- You flashed the right bootloader for pic18f4685 => bootloader_v1_2b_pic18f4685.hex
- And upload the right MIOS with MIOS Studio => mios8_v1_9h_pic18f4685.hex

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Posted (edited)

Ok, I did the lcd interconnection test. I refused to, because I don't understand what's the difference vs signal checking with a Voltmeter.

But first, results:

Sending 5v at d4 gives me just 1.65v and d5 has 0.8v

Sending 5v at rs = 0.20v

And now, I don't understand why the Voltmeter tells me the lines are not touching each other.. because of touching in a microarea?

Update, solved.

Thank you!

Data lines are more sensitive, right? I removed also the bridge pin 28 to j4.

Also I put in the 1k resistor and diode for can Interface bevor but Im kind of sure it's not necessary for the LCD connection.

Update,

Checked the second Core and rs just gave me, 0.80v. I was kind of sure it´s the connection to r4, cutted the wire and voila.

So, I still did not make an research by my own and maybe I overlooked something but either r4 is removed for the x4685 or I did a mistake. 

Edit. Yes I soldered the bridge to the wrong pin at j4 at both cores...shame...sha...

 

 

Edited by Noise-Generator

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