AN48303 discusses the compatibility issues that you should consider before migrating from CapSense® Express™ firmware revision 0x15 to 0x1B.
Introduction
CapSense® Express™ supports up to 10 I/Os that can be configured as capacitive sensing inputs or digital GPIOs. These configurable I/Os are used for operations, such as interrupt, wakeup line, and PWM output.
Firmware Rev 0x1B provides an enhanced performance and introduces several features, which need particular attention when migrating from an existing project that uses Rev 0x15.
In this document, CapSense Express Firmware enhancements are not explained in detail. Instead, this document deals with the effects of the enhancements on the register and device accessibility.