Introduction:

When starting a new BBB with one of the images released on Beagleboard.org,  the Power Management IC charge voltage is set to a default of 4.1V and for certain applications we might want to increase the charge voltage to the maximum of 4.2V. This can be done by accessing the PMIC register with I2C tools and changing the set values according to the data sheet located here :

https://www.ti.com/lit/ds/symlink/tps65217.pdf?ts=1675319719718

BeagleBone Black I2C Tools:

BBB (BeagleBone Black) I2C tools are a set of software utilities that allow the user to interact with I2C devices connected to the BBB. These tools are essential for accessing, configuring and modifying the I2C devices connected to the BBB.

Accessing the PMIC (Power Management IC) using BBB I2C Tools and changing the charge voltage:

Identify the I2C address of the PMIC. This can typically be found in the device datasheet or by using an I2C scanner tool:

i2cdetect -l

• Lists the i2c busses detected on your beaglebone.
• PMIC is on i2c bus number 0.

Run the following command to change the charge voltage to 4.2V:

?i2cset [-f] [-y] [-m mask] [-r] i2cbus chip-address data-address [value] ... [mode]?

sudo i2cset -f -m 0x30 0 0x24 0x05 0x20

• This will write to device file /dev/i2c-0, chip address 0x24, data address 0x05 (CHGCONFIG2), data 0x20 (masked), mode byte.
• The default value is 0x80 (1000 0000)
• We then change this to 0x20 (0010 0000) as per the data sheet linked above (see snippet below).