Hi to all.
I'm watching if it is possible to run with a single arduino module up to 10 or more lcd display by I2C bus.
Nothing complicated, the displays show fixed program's name of a multiple footswitch controller, every footswich match a program, and so every footswitch has a display that shows the name of the program.
I've seen that the adapters I2C have three jumpers used for modify adress by soldering, so if i buy eight of this, i have 8 different adresses.
To command the other display to reach number of 10 , i'm searching different adapters I2C, that by using also with this the soldering jumpers, result different adresses respect the previous eight.
I think that , regard the different adress with I2C bus , is possibile because number of avaibile adressese is more and more than 10.
Do you think, that if i could find different I2C module adapters,( different manifacturer for example) for obtaing more than 8 adress, it will works?
thanks and sorry for the bad english language.
Welcome to the forum.
It is possible. Which Arduino board do you use ? Do you have a picture of a example what you want to build ? I remember similar projects with OLED displays.
Here are three of the many options:
Trying to find displays with different address range might cause trouble. If you want to build another project or replace the displays, then you need to find that specific set of displays 
Using a I2C multiplexer: https://www.adafruit.com/product/2717 is always a good option 
My suggestion is to use more than one software I2C buses 
By combining the SCL, only 11 pins are needed if they all have the same I2C address. By assigning different I2C addresses for the displays, only two I2C buses are needed, that is 3 pins with a combined SCL.
The software is not that easy. You need a LiquidCrystal library that accepts other I2C buses and not all software I2C libraries are compatible at that level. But there are a number of solutions. At this moment, there is work being done for this situation to make it possible without a hassle.
Changing the source code of the LiquidCrystal library to use a software I2C library is a hassle, but it works. Here is an example of that with 30 I2C buses: manyI2Cbuses.ino - Wokwi Arduino and ESP32 Simulator
about which LCD's are you talking? Character LCD with PCF8574? The PCF8574 comes in two variants with different base addresses ( 0x20 - 0x27 or 0x38 - 0x3F );
Therefore up to 16 LCDs can be used very easily.
Please show the product you have.
Yes, you can use 8 PCF8574 addresses 0x20-0x27
And 8 PCF8574A addresses 0x38-0x3F
Note that the backpacks come with and without 4k7 pullup resistors.
You only need one pair for all 10 backpacks.
It will be ok for up to 3 pullups e.g. 1k6
10 pullups will be too much for the I2C bus.
David.
Hi thanks for you gentile responses. I Will try and update as soon as possibile.
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