MBR3xxx is pre-programmed with fixed firmware. If users want to tune it, they only need to configure some parameters through I2C master command, or using EzClick(a GUI tool on PC).
We have an MBR3 EVK, here is its link. FYI.
In addition, MBR3 is very suitable for some simply applications in general environment (Temperature and humidity changes slowly, commertial marketing). If the customer would like to use CapSense functions more flexibly(some extreme environmental conditions, white goods, industrial, automotive applications), it is recommended to select PSoC4 or PSoC6 series. With using these parts, customers can customize their code(firmware) to meet their specified requirements.