Setting the I2C address - Funduino LCM1602 I2C Backpack

I looked all over the web for information pertaining to this board as to if I could change the I2C address on it. I could not find my specific one so I loaded an I2C scanner sketch and tested what I thought were address jumpers on the back of the module. There are 6 holes in a 3x2 pattern which can accept a pin header or you can simply use a section of 22ga wire to jumper it.

Here is my board:



I will represent the jumpers by brackets. The jumpers are installed in columns. For example: to set 0x24, you will jumper column 1 and column 2.

0x27
[] [] []
[] [] []

0x26
[/] [] []
[/] [] []

0x25
[] [/] []
[] [/] []

0x24
[/] [/] []
[/] [/] []

0x23
[] [] [/]
[] [] [/]

0x22
[/] [] [/]
[/] [] [/]

0x21
[] [/] [/]
[] [/] [/]

0x20
[/] [/] [/]
[/] [/] [/]

I hope this can help someone else.

 

I cannot take a photo of the bottom as it is soldered in. However, a quick look underneath shows what appear to be 3 SMD resistors mounted just to the left of the 6 holes. The bottom 3 holes are all common and the top ones go to pins. The common trace goes to the backside through a via and is connected to a resistor. Whether or not the single resistor takes care of the pull up or pull down, I am unsure.

*edit*

After more investigation I am certain that the single resistor takes care of the pull up/down. The top 3 connections go straight to pins on the expander. I came to this conclusion by holding the board to a light and shining through from the underside so as to see the top traces.

 

It could be. I tried once to desolder this board so I could solder female pin headers on it and use it on other boards but could not get the solder to give up. Otherwise I could have gotten a photo of it.