I2c multiple devices not recognized

[mrfop]

@Koepel

This is your Issue ? https://github.com/ricaun/DuinoCoinI2C/issues/49 .

Yes it is.

@Koepel

It uses Wire.begin() a lot, but that should only be used in setup().

I removed all wire.start(); which contains the .begin. No improvement in behaviour.

@Koepel

It seems to read one byte per I2C session. That is also weird. The Slave has no "time to breathe", see my notes about Arduino in Slave mode.

I added a random delay to clients_loop(). No improvement in behaviour.

@Koepel

It starts looking at I2C address 1.
There is some random delay, in case all the Slaves are powered up at the same time. That random delay uses 9 bytes from the signature data (manufacturer data inside the Nano). Those signature bytes might be the same.

Where do you see that? I only noticed that getTrueRotateRandomByte() reads the input of A1.
I replaced the power-on delay with a regular delay(random(10,500)); No improvement in behaviour.

@Koepel

Can you explain what is going on ?

Do you mean explain the code? I'm fairly new to this stuff, I need to understand it first

@Koepel

What do you mean if you power it on often enough ?

I power it on --> no Slaves in list of Master. I power it on so many times until the Slaves appear in the list.

@Koepel

Can the Master print a list of Slaves ? To be sure that the Master sees 10 Slaves.
Was the project on Github only done with 6 Nano boards ? and never more ? Then it could be a in the code, for example an array that is too small.

Yes it can. The List is then numbered from 0 to 9. There is #define CLIENTS in DuinoCoin_Clients.ino and I guess also #define WIRE_MAX 32 in DuinoCoin_Wire.ino (?).
Couldn't find an array that is too small. When it works it works for all devices.

@Koepel

Is there something else connected to the I2C bus ? For example a OLED ? OLED display have the habit to disturb the I2C bus for others.

I removed the oled code. No improvement in behaviour.

What helped me today to get it all started without powering on the whole thing many times is to reset the Arduinos one by one. Then everything is fine...
Maybe I should add a random reset