Can't start Chinese OLED 1.5" 128x128 SSD1327

[nicolas.reau]

Hi!

I'm tying to make this project: Arcade Button midi controller and now everything is working, except the OLED display. I am in China and I couldn't fin the same exact OLED, so I bought what I thought was the most approaching: https://item.taobao.com/item.htm?spm=a1z09.2.0.0.21e22e8dAEzKhS&id=568527842788&_u=q1s69o9d3f96

Of course it doesnt have the very convenient Stemma connector, and by default is set up for SPI not I2C, but hey, I'm here to learn

ZJY150S0700WG01.pdf (1.5 MB)

I tried to start it using adafruit ssd1327 library examples (with an Arduino UNO initially) and the recommanded connection:

The documentation initially led me to think that to switch to I2C I would just need to move a resistor from R4 to R5, and ground DC and CS. It never worked. Then I noticed that the table also suggested that i2C R3 should be mounted, and I think it is 0R according to the schema so I soldered a jumper. Same result. The screen just always stays black.

I also try different codes to detect i2c devices and it could usually detect it on the expected address (0x3d or 0x3c).

Now, if I solder it to the Rasp Pico as per the adafruit project, it stills not starting, and the log says it can't find anything at the address that it looks at (0x3d by default but I also modified to try to look at 0x3c).

The OLED looks like this in front:

And back:

I know my welding is dirty I will try to do it cleaner again, however except for the R4, I also tested a lot with regular dupont connectors before soldering the cables (this is to plug to the rasp because no stemma connector).

I don't know what i am missing and the vendor is absolutely unhepful ("You cna try!" is his answer to all my questions) =)
I also tried Larry's SSD1327 library, same result.

Do I understand the necessary connections right?
-R4-> R5 and jumper on R3 (or 0R) + ground DC and CD
-then connect VCC, GND, SDA, SCL?
-what about the reset pin?

Thank you I you can point me to some direction, it'a bit of a big and advanced project for me and it's quite frustrating to be stucked so close to finishing it (I cam play midi notes and have the light buttons, just the nice OLED display is missing)

Cheers
Nicolas

[garyoldman92]

hi nicolas, sorry for my English.
I have this problem too,but i found solve.
on point after diode vd1(vcc15v look scheme), must be +15v. But this point does not have needed voltage. i puted +15v from my power supply on this place. i united gnd display and gnd power supply. And.... and display is alive. i added photo.

seems i understood why display dosn't work. divider dc-dc(step up) setted wrong.
Good luck.

[garyoldman92]

i'm new user and can upload 1 photo to 1 message.
Add reverse side display

[nicolas.reau]

Hi Gary,

Yes, I think you are right, there is definitely a problem with the supply! It should be possible to power it up with 3V as I understand, but I only got it working when plugging it to the +5V from the raspberry pi (fortunately available!). And my display is not as bright as yours with +15V, so maybe these 5V are even barely sufficient.

Also the first OLED had an edged cracked so I got it replaced... overall cheap quality, but also a cheap price

[garyoldman92]

Yep, you are right. I have display with i2c from another manufacturer, it's work well with +5v and +3v. On the previous board I've changed resistive divider, after out step-up dc-dc and diplay light up good. In future i'll design my own board with dc-dc.I think it will be the cheapest.