OLED 1.3" SSD1306

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asknik2022
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Joined: 26/03/2022
Location: United Kingdom
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Posted: 03:32pm 21 Mar 2023      

I have a OLED SSD1306 1.3" I2C which works perfectly using gp0,gp1

I have a OLED SSD1306 1.3" SPI/I2C which I have soldered modified to I2C as per instructions on back of display
I have connected as follows
GND >> GND
VCC >> VCC
SCL >> CLK
SDA >> MOSI

But I get nothing.

Do I need to connect RES,DC,CS, and if so where to.
Edited 2023-03-22 01:33 by asknik2022
Pluto
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Posted: 03:45pm 21 Mar 2023      

Yes you have to connect all. See the p.44 in PicoMite User Manual MMBasic Ver 5.07.06 (if you are using PicoMite).
asknik2022
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Posted: 04:03pm 21 Mar 2023      

This is all it says on page 44 about I2C SSD1306

OPTION LCDPANEL SSD1306I2C, OR [,offset]
Initialises a OLED display using the SSD1306 controller with an I2C interface. This supports 128 * 64 resolution.
An additional parameter offset may be specified to control the position of the display. 0.96" displays typically
need a value of 0. 1.3" displays typically need a value of 2. Default if omitted is 0.

I have converted the display from SPI to I2C so shouldn't I be using
OPTION LCDPANEL SSD1306I2C,L,2
Pluto
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Posted: 04:23pm 21 Mar 2023      

Pluto
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Posted: 04:28pm 21 Mar 2023      

Check:
https://geoffg.net/picomite.html
for the latest manual.
Mixtel90

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Posted: 04:50pm 21 Mar 2023      

If it's been converted from SPI to I2C then I can't see why the SPI information is relevant.

As far as I can see the connections are correct. VCC goes to 3V3. None of the other pins are used by I2C, but connect RES to 3V3 and the other two pins to GND.

Did you remember to short out R8?

Are there any pullups on SDA and SCL? It may be worth trying 10k for these.


Info from https://www.instructables.com/OLED-Tutorial-Convert-SPI-to-I2C/
Pluto
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Location: Finland
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Posted: 05:17pm 21 Mar 2023      

Sorry for the confusion
I understood that you had it working with I2C and wanted to change to SPI.
asknik2022
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Joined: 26/03/2022
Location: United Kingdom
Posts: 80
Posted: 07:47am 22 Mar 2023      

I managed to get this working by using an ESP8266 and prgrammed it via Arduino IDE
However I had to connect RES to the reset pin in order to get it to work.

I would prefer to use the pi pico but there is no reset pin.
On the Pi Pico connecting the RES to VCC(5v or 3.3V) all I get is full screen of dots.

??
Edited 2023-03-31 02:36 by asknik2022
asknik2022
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Location: United Kingdom
Posts: 80
Posted: 04:37pm 30 Mar 2023      

Can anybody help me on this please


I managed to get this working by using an ESP8266 and prgrammed it via Arduino IDE
However I had to connect RES to the reset pin in order to get it to work.

I would prefer to use the pi pico but there is no reset pin.
On the Pi Pico connecting the RES to VCC(5v or 3.3V) all I get is full screen of dots.
matherp
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Posted: 04:51pm 30 Mar 2023      

Have you tried with the latest beta?
asknik2022
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Posted: 05:15pm 30 Mar 2023      

YEP
phil99

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Posted: 09:43pm 30 Mar 2023      

"I would prefer to use the pi pico but there is no reset pin."

The RUN pin is a "Not Reset" pin. Pull it low and the Pico resets.

PS. A 100nF from RUN to Gnd. can prevent unintended resets.
mozzie
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Joined: 15/06/2020
Location: Australia
Posts: 68
Posted: 12:32am 31 Mar 2023      

@asknik2022
Some of those OLED have a jumper to select I2C address on the back, to select from &h78 and &h7A (0x78 / 0x7A)
All the units here are set to &h78 and work with MMbasic so might be worth checking on the unit you have there.

Another suggestion is to try an R/C network on the reset of the OLED, try 10k to +V and 2.2uf to ground, with SPI the reset is driven but using I2C it's not from MMBasic.

Regards,
Lyle.
Edited 2023-03-31 12:10 by mozzie
Mixtel90

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Posted: 06:15am 31 Mar 2023      

Or just put reset to any pin and pulse it before accessing.