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vincenthimpe
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Joined: 14/10/2018
Location: United States
Posts: 45

Posted: 09:37pm 26 Apr 2025

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basic version 6.0001 , rpi2040

The manual says many modules are wired wrong without explaining exactly what is wrong. It's also not explained what base address the built in routines expect. (0x3c or 0x3d)

Display is attached to physical i2c1 (not i2c0)

option system i2c gp18,gp19 ' i2c1 port as system port
option lcdpanel ssd1306i2c,1,2

i2c2 check &h3c ' returns 0 so the device is there

comment : the naming of the i2c devices is confusing.
i2c means physical i2c0
i2c2 means physical i2c1

i rewired the display to 0x3d and
i2c2 check &h3d ' returns 0 if display wired to 0x3d

Nothing appears on the display.
Tried line and text commands.

it would be good to be able to set the base address for the system display.
like:

option lcdpanel ssd1306i2c,1,2 ,&h3c
option lcdpanel ssd1306i2c,1,2 ,&h3d

any ideas ? any leads on what displays are known to work. ( 1.3inch. need 128x64 )
Thanks

matherp
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Joined: 11/12/2012
Location: United Kingdom
Posts: 9992

Posted: 09:47pm 26 Apr 2025

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Quote The manual says many modules are wired wrong without explaining exactly what is wrong.

What's wrong is they don't work. 0.9" displays are typically fine. 1.3" are typically not although I have had some in the past that have worked. No idea why.

vincenthimpe
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Joined: 14/10/2018
Location: United States
Posts: 45

Posted: 10:23pm 26 Apr 2025

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most of them seem to use a SSD1315 controller. Looks like the 1306 can't drive the larger oled ( not in pixelcount, but actual pixel size. it takes more current)

studying datasheets now...

looked through the mmbasic sourcecode . looks like 0x3c is the expected base address.

vincenthimpe
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Joined: 14/10/2018
Location: United States
Posts: 45

Posted: 10:36pm 26 Apr 2025

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Is there a way to trigger the init sequence using a command ? The display init only happens during power cycle.

i want to trigger "InitDisplayI2C" from the interpreter.
same for I2C_Send_Command and i2c_send_data.

that way i can experiment with initializing the controller.

i could rewrite that code in mmbasic, but if the functions exist it would be faster.

thanks

bigmik

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Joined: 20/06/2011
Location: Australia
Posts: 2944

Posted: 03:54am 27 Apr 2025

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Hi Vincent,

Many moons ago I designed a PCB called >>> Serial Backpack <<< that took serial commands to display onto various LCD modules (to alleviate the load on the main Controller).

John Gerrard aka JMan on TBS wrote some drivers in C to support various modules SSD1306 was one of them.

In the link above you might find clues to what you are after. The Serial backpack was based on a MX170 so the C code wont work but if you contact John he may have the source files or you may be able to clean some info from his basic drivers in the above directory.

Unfortunately I don't speak "C" so cant help you directly.

Kind Regards,

Mick (The big one)

.

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

Mixtel90

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Joined: 05/10/2019
Location: United Kingdom
Posts: 7458

Posted: 08:46am 27 Apr 2025

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I use the SSD1306 I2C 128x64 on my fish tank controller. It works fine. These are some I got from AliExpress. I'm using I2C0 on GP0/GP1 but I can't remember the I2C address offhand.

The naming of the devices isn't confusing if you want compatibility with MMBasic platforms that only have a single port called "I2C". If the PicoMite had used I2C0 and I2C1 (as the Datasheet does) none of the software that uses "I2C" would have run without modification.

Mick

Zilog Inside! nascom.info for Nascom & Gemini
Preliminary MMBasic docs & my PCB designs

mozzie
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Joined: 15/06/2020
Location: Australia
Posts: 90

Posted: 08:51am 27 Apr 2025

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G'day Vincent,
Please also be aware that some "SSD1306" Oled displays are really using the SSH1106 controller

they also share the same IIC address

The SSD and SSH are very similar and if memory serves correct, can be got to work with some commands sent.

I found this out the hard way when the SSD1306 displays I purchased refused to work

am away from main PC for a couple of days but will be able to confirm when home.

Regards,
Lyle.

matherp
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Joined: 11/12/2012
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Posted: 09:16am 27 Apr 2025

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Quote most of them seem to use a SSD1315 controller.

Thanks for the hint. I've changed the initialisation to suit the both the 1306 and 1315 so it should work in the next release with the command

OPTION LCDPANEL SSD1306I2C,L,2

matherp
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Posted: 09:40am 27 Apr 2025

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If you download RC18 again the fix is now in it. Please try it and report

vincenthimpe
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Joined: 14/10/2018
Location: United States
Posts: 45

Posted: 06:08pm 27 Apr 2025

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it works ! thanks a lot !
small request for next release candidate :
- add a way to trigger the init routine using a command
- add a way to switch addresses (3C and3D)

something along the lines of

SSD1306I2CINIT &h3C
SSD1306I2CINIT &h3D

SSD1306I2CTARGET &h3C
SSD1306I2CTARGET &h3D

you don't need to alter the commands.
It looks like the 3C address is defined as a constant in the .h file.
make it into a variable and have a command to set the target.
this would enable the use of two displays

Some board have the address bit switchable.

i had to bodge mine on the flex as the D2 trace was hard strapped under the flex.

trial code:

PicoMite MMBasic RP2040 Edition V6.00.02RC18
OPTION SYSTEM I2C GP18,GP19
OPTION CPUSPEED (KHz) 200000
OPTION LCDPANEL SSD1306I2C, LANDSCAPE, 2

Attached display with ssd1315 (1.3inch oled):

https://goldenmorninglcd.com/oled-display/1.29-inch-oled-128x64-ssd1315-gme12864-77/

sold on amazon
https://www.amazon.com/dp/B09ZP6MLWR?ref=ppx_yo2ov_dt_b_fed_asin_title&th=1

i ordered a bunch of different ones. to see what is out there. will update this post with findings

Edited 2025-04-28 04:16 by vincenthimpe

vincenthimpe
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Joined: 14/10/2018
Location: United States
Posts: 45

Posted: 04:25pm 29 Apr 2025

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Additional Display tested (i have mor eon the way)

Panel maker : Univision technology / Wisechip
format : 128x64
bus : i2c 0x3c
Flex marked UT-0205-P05
Size : 2.4 inch
Controller: SSD1309
Status : WORKS

Panel maker : unknown
format : 128x64
bus : i2c 0x3c
Flex marked NFP1315-61AY
Size : 0.96in
Controller: SSD1315
Status : WORKS

Panel maker : unknown
format : 128x64
bus : i2c 0x3c
Flex marked NFP1315-45AY
Size : 0.96in
Controller: SSD1315
Status : WORKS

Panel maker : unknown
format : 128x64
bus : i2c 0x3c
Flex marked -blank-
Size : 0.96in
Controller: SSD1315
Status : WORKS

will update with pictures, datasheets and source

vincenthimpe
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Joined: 14/10/2018
Location: United States
Posts: 45

Posted: 07:05pm 29 Apr 2025

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Panel maker : Goldenmorning
format : 128x64
bus : i2c 0x3c
Flex marked GME12864-98
Size : 1.54 inch
Controller: SSD1315
Status : WORKS but needs offset 0 during init

Panel maker : unknown
format : 128x64
bus : i2c 0x3c
Flex marked XFP1116-07AY
Size : 1.3 inch
Controller: SH1106
Status : WORKS

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