X9C103 digital potentiometer with EEPROM stored initial value

      I received few X9C103 digital potentiometer modules with 10kΩ and I need to prepare it for tests:

 

   I used this schematic:

where in A0 is voltage fron wiper of potentiometer (as a resistive divider for 5V power supply) and also I read 5V voltage in A0 (to check if is 1023).

   In the previous tests with a remote contributor X9C103 potentiometer not store value in NVM, so I used an oscilloscope to saw the signals... the signals are ok, but chip not store the value in NVM (non-volatile memory):

so I used EEPROM memory from Arduino Nano board (ATmega328P chip).

   Last sketch is pot_X9C103_1_1.ino. and in this sketch it used LapX9C10X library (also X9C103 chip "not want" to store the value using writeNVM() command from this library).

   I upload the X9C103 digital potentiometer with EEPROM stored initial value where you can see how sistem works:

Bibliography: article in romanian language - Teste cu potentiometrul digital X9C103 (10kΩ) !

MCP4261 dual digital potentiometer

   I have an MCP4261-503E/P dual digital potentiometer hwo can control via SPI interface in 256 steps (0 to 255 - 8 bits).

   I use info find in article Arduino - Using digital potentiometers part 2 (MCP4251) from Matthew McMillan's blog.
   My digital potentiometer is in THT/PDIP capsule:

   After info from Mattew's sketch I made my test schematic:

and after made some changes, I upload MCP4261_mega_lcd1602_i2c_test.ino sketch.

   For tests, I have some particular cases:

- both on minimum 

- first potentiomer at minimum and second at maximum:

- first potentimeter at maximum and second at minumum value:

- both at maximum:

and after that I put to change steps from 0 to 255 to see the difference between potentiometers:

   I put on net 2 movies:

-  MCP4261 digital dual potentiometer with Arduino Mega:

- MCP4261 digital dual potentiometer with Arduino Mega (2)