Hey,
I’m a little bit of a newbie to the Particle Photon and I have been trying to hook up a Photon to an Adafruit OLED SSD1306 0.96" 128x64. I should say that I haven’t just come crying without looking for other posts and topics. I have tried using the rather good library from @peekay123 without any luck. By which I mean the program compiles and runs from Particle Dev and I can even run the Adafruit I2C .ino file and get a serial output from the Photon. However, the OLED does not actually load any graphic or text. I’m out of ideas and would appreciate some help.
Wiring:
Data: D0
Clock: D1
Vin: Vin
Rst: D4 (I have tried without D4 too)
Thanks,
Sam
Have you selected I2C by soldering the jumpers on the back of the board?
Have you set the correct I2C address in your code (depending on your SA0 state)?
This schematic mentions addresses 0x78 & 0x7A while the product page mentiones 0x3C & 0x3D
https://learn.adafruit.com/assets/36493
(I guess the 0x7# is the 8bit address including R/W bit0 and 0x3# is the same address shifted 1bit right)
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@Sammy_Herring and to add to what @ScruffR said, did you add 4.7K to 10K ohm pull-up resistors to both the D1 and D0 I2C pins?
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Looking at the schematics there should be 10k pull-ups on the shield, but another set of 10k should not harm.
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Hey @ScruffR and @peekay123,
Thank you for getting back to me so quickly!
I worked through what @ScruffR had mentioned about the jumpers. But I had not changed the schematic address. I tried 0x3D which works for the 128x64 and the 0x3C works for the 128x32.
So yes, it now works!
Thank you, however, would it still be worth adding pull-up resistors to the I2C pins? May I also ask what the purpose of the Reset pin is (if you know)?
Thanks,
Sam
If it works without them (or rather with the 10k on-board ones alone) there won’t be any benefit in adding a second set.
Update
One purpose of the reset pin on the display whould be to help getting the display back in a known state in case it hangs for some reason.
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Ok, not a problem and thank you. May I also ask what the purpose of the Reset pin is (if you know)?
Ok - great to know - Thank you!
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