This is my first build. Things have been going surprisingly smooth. Finished testing audio and led. To my delight everything checks out. Hook up the lcd and there is problems. If you look at the lcd straight it appears as if its not on. If you look from the side angle it appears slightly illuminated. Help! Meanwhile this piece of candy just stares at me laughing inside.
Have you adjusted the contrast trim pot?
I presume you are making a Shruthi from a kit?
Also, check that all solder points to/from the lcd are good. Check for cold joints or shorts between pins.
As I recently have had the same “trouble”,
with display on midialf,
you have 2 turn the LCD-poti “very often” 2 see letters arrive.
Is the backlight on or off? Maybe you could post a picture… What have you soldered as the R_LCD resistor?
Lcd is emitting some light. Most noticeable if held at an angle. Here is an above shot. Sorry for the clarity. I snapped a few quick ones on my way to work.
Not a great photo but at least you can see the light emitting on the bottom of the lcd
You MUST BE XTREMELY CAREFULL not to touch with the voltage regulators the the digital board - else you might damage/destroy/trash your digital board!
See Part11 of the Instructions
As i cant see any spacers between the board i fear exactly this happened and you killed your ATMega or something…
When testing the only parts that touched were the midi in and out housing and maybe the top corner of IC9 on the filter board.
IC9, the 7805, is a voltage regulator, also known as the bringer-of-instant-death-to-certain-chips-on-the-digital-board-if-it-contacts-something thingy.
IC 9 actually is the 7805 posiitve Voltage regulator… do your Knobs work as expected? does your unit respond to MIDI?
Actually the 7805s Metal Part is connected to GND, so its not as worse as the 7905 whose Metal Thingie is connected to the negative PSU Rail coming from the 1054 that has that instantkilling -(whateveryourPSuprovides + 1) Volts
First thing to do: power off. Next, either mount the spacers between the two boards or at least slide a piece of cardboard between the two boards so nothing on one board can touch anything on the other. Then power up again, and check if the leds react to button pushes and encoder actions as you would expect. If they do, you were lucky and should go on to adjust the lcd contrast (if they don’t, you’ll have to replace the 74HC595 IC and possibly the 74HC165. At least you socketed them). For adjusting the contrast, turn the trimmer on the digital board an incredible number of turns in one direction, then if nothing shows up, an incredible number of turns in the other. Incredible is something like fifty half-turns (when you adjust the trimmer you’ll probably be able to make just half turns).
I will test it out when I get home from work. Im hoping for the best but planning for the worst. We can I buy replacement components.
The nobs and buttons seem to work.
What have you soldered as the R_LCD resistor?
Where is the R_lcd located?
The one rght beside the MIDI Ports, above the ATmega.
And before you ask - no you cant measure it in circuit, here a table to decode the funny rings:
Ill look when I go home but im almost positive its the orange orange black silver. I kept searching over and over for the first part referenced until I realized the additional info that mentioned the orange orange black silver
If you have a kit all your Resistors should have 5 rings and be blue.
This is whats going on below the lcd. The audio seems fine. Just no LCD. What are my options for fixing