@martin_triska Thank you for this answer :)

As you can see the addresses of both MCP23008 are visible.

0x20 for the MCP23008 on the Unipi 1.1 board
0x22 for the MCP23008 of the EMO-R8 expansion board

And both boards have their own power supplies purchased from Unipi (CLW-1005-W2E-EB) of 5V in 2A.

And with or without, it doesn't matter...

So I made a new RJ11 cable and it worked :)

Life is simple especially with a good connection....

ONLY in English ...

Hello,

I have a Unipi 1.1 card and an 8 relay extension EMO-R8.

I can drive the Unipi card (I2C address 0x20).
The EMO-R8 module is configured to I2C address 0x22.

But unlike the relays on the Unipi board, I can't do anything with the EMO-R8 module.

Nothing happens :(

Here is my program which works perfectly with the Unipi 1.1 board:

#!/usr/bin/python

#
# Testing relays
#

import smtplib
import math
import smbus
import time

# Open the bus
bus = smbus.SMBus(1)

# Force output ports
bus.write_byte_data( 0x20, 0x00, 0x00 )

wait5s=5
wait=0.125

# Activates relays and switches them off 
for value in [0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80]:
    bus.write_byte_data( 0x20, 0x09, value )
    time.sleep( wait5s )

# Activates relays and switches them off 
for value in range(0,80):
    bus.write_byte_data( 0x20, 0x09, value )
    time.sleep( wait )

# Activates relays and switches them off 
for value in range(80,0, -1):
    bus.write_byte_data( 0x20, 0x09, value )
    time.sleep( wait )

# Activates relays and switches them off 
for value in [0x80,0x40,0x20,0x10,0x08,0x04,0x02,0x01]:
    bus.write_byte_data( 0x20, 0x09, value )
    time.sleep( wait )

# Force ports to zero
bus.write_byte_data( 0x20, 0x09, 0x00 )

See the list of I2C addresses used :

root@raspberrypi-002:/home/pi# i2cdetect -y 1
     0  1  2  3  4  5  6  7  8  9  a  b  c  d  e  f
00:          -- -- -- -- -- -- -- -- -- -- -- -- --
10: -- -- -- -- -- -- -- -- 18 -- -- -- -- -- -- --
20: 20 -- 22 -- -- -- -- -- -- -- -- -- -- -- -- --
30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- --
50: 50 -- -- -- -- -- -- 57 -- -- -- -- -- -- -- --
60: -- -- -- -- -- -- -- -- 68 -- -- -- -- -- -- 6f
70: -- -- -- -- -- -- -- --

This gives in readable form :

Chip 			Adress		Usage			Board
-----------------------------------------------------
DS2482-100		0x18		1Wire master	Unipi 1.1
MCP23008		0x20		Relays			Unipi 1.1
MCP23008		0x22		Relays			EMO-R8
24AA00/24C02	0x50-0x57	EEPROM			Unipi 1.1
MCP79410		0x57,0x6F	Real time clock	Unipi 1.1
MCP3422			0x68		ADC				Unipi 1.1

root@raspberrypi-002:/home/pi/unipi# i2cdetect -l
i2c-1   i2c             bcm2835 (i2c@7e804000)                  I2C adapter

When I operate the Unipi relay ports :

I have activated the MCP23008 (on the Unipi 1.1):

It works perfectly :)

Initialisation of port 0x20 (Unipi 1.1) :

root@raspberrypi-002:/home/pi/unipi# i2cset -y 1 0x20 0x00 0x00

root@raspberrypi-002:/home/pi/unipi# i2cset -y 1 0x20 0x09 0x01
root@raspberrypi-002:/home/pi/unipi# i2cset -y 1 0x20 0x09 0x00

How to use port 0x22 (EMO-R8) ?

Because the following does not work :(

Initialization of port 0x22 :

root@raspberrypi-002:/home/pi/unipi# i2cset -y 1 0x22 0x00 0x00

root@raspberrypi-002:/home/pi/unipi# i2cset -y 1 0x22 0x09 0x01
root@raspberrypi-002:/home/pi/unipi# i2cset -y 1 0x22 0x09 0x00

Do I need to do anything special to make the EMO-R8 modules work ?

I know, that there are Unipi solutions via their programs. But, I want to be free and not use a program that will have difficulty interfacing with other programs specific to my needs.

That's why I prefer to access the controllers directly and do exactly what I want.

Thank you for your help :)

JB