Follow the bq28z610EVM 1- to 2-Series Li-Ion Battery Pack Manager Evaluation Module users guide to get started with hardware connections and basic gauge setup.

The charger must have a 2-byte charge current and charge voltage register, it must not have any other bits in the same register used to configure the charger. The gauge will write the whole 2-byte register, so any configuration information would be overwritten. If the bits are reserved, it does not matter what the gauge writes to the register.

The BQ25730 is an I2C-based charger that has 2-byte charge current and voltage registers, the BQ28Z610-R1 can be configured to work for this charger.

The BQ25730 is compatible with the BQ28Z610-R1 broadcast mode because the register is 2-bytes and the unused bits are reserved, not configuration bits. The device address should be set to the 7-byte address without the read/write bit. Set the Voltage and Current registers to the beginning register value. For example, if charge current is 0x02-0x03, set it to 0x02. The pacing should be set to prevent a charger watchdog from clearing the values written by the gauge.

To setup the BQ28Z610-R1 to communicate with the BQ25730, the Device Address should be set to 0x6B, which is the 7-bit address without the read/write bit. The current register should be set to address 0x02, and the voltage register to address 0x04. The watchdog resets the charger every 175 seconds by default, so the pacing should be less than that value.