All the latest C2000 devices use a defined set of GPIOs to allow for boot mode selection upon device power-on or reset. This is accomplished by the boot code decoding the state, whether pulled high or low, of the GPIOs. Once decoded, the interpreted value is used as an index to select which boot mode from the boot mode selection table should be run. The GPIOs used as boot mode select pins have typically been locked to their default GPIO. Starting with the Delfino F2837xD devices and carried over to future devices, the GPIOs used as boot mode select pins are now configurable. On F28004x onwards, writing to the BOOTPIN_CONFIG memory location in user-configurable dual code security module (DCSM) OTP allows for all three of the possible boot mode select pins to be set to almost any GPIO available on the device. Devices are no longer locked to the factory default GPIOs, which allows for a greater flexibility in terms of pin usage.

C2000 devices have not only required a certain set of GPIOs to use as boot mode select pins, but a specified number of pins themselves. The number of boot mode select pins used either expands or restricts the available boot modes selectable in the boot table. If there are four boot mode select pins used, there can be up to 16 boot options selectable, but if only two boot mode select pins are used then only four boot options are selectable. On F28004x device onwards, the factory default setting is two boot mode select pins but the number of pins can be customized to support as many as three pins and as few as 0 pins. Using options such as 0 boot mode select pins, provides only a single boot mode to be selected but also frees up the other pins to be repurposed. If many boot modes are required for various scenarios, then using three pins will allow for selecting between eight possible boot choices. Disabling any particular boot mode selection pin uses the same BOOTPIN_CONFIG memory location as when changing the GPIO number used except now a value of “0xFF” is written to disable that specified pin.