SWRA466E February 2015 – August 2024 CC1310 , CC1310 , CC1311P3 , CC1311P3 , CC1311R3 , CC1311R3 , CC1312PSIP , CC1312PSIP , CC1312R7 , CC1312R7 , CC1314R10 , CC1314R10 , CC1352P , CC1352P , CC1352P7 , CC1352P7 , CC1352R , CC1352R , CC1354P10 , CC1354P10 , CC1354R10 , CC1354R10 , CC2538 , CC2538 , CC2620 , CC2620 , CC2630 , CC2630 , CC2640 , CC2640 , CC2640R2F , CC2640R2F , CC2640R2F-Q1 , CC2640R2F-Q1 , CC2642R , CC2642R , CC2642R-Q1 , CC2642R-Q1 , CC2650 , CC2650 , CC2650MODA , CC2650MODA , CC2651P3 , CC2651P3 , CC2651R3 , CC2651R3 , CC2651R3SIPA , CC2651R3SIPA , CC2652P , CC2652P , CC2652P7 , CC2652P7 , CC2652PSIP , CC2652PSIP , CC2652R , CC2652R , CC2652R7 , CC2652R7 , CC2652RB , CC2652RB , CC2652RSIP , CC2652RSIP , CC2674R10 , CC2674R10
The built-in bootloader on the CC2538, CC13xx, and CC26xx devices starts running after a power-on reset if there is no valid application image in flash, determined by an image valid field in the customer configuration area (CCA) or , customer configuration (CCFG). For more information about the image valid field in CCA or CCFG, see the following documentation for each device family:
Alternatively, the bootloader starts if the so-called bootloader backdoor is enabled and the associated pin that opens the backdoor is set to the correct logic level. If the bootloader is activated, the bootloader is ready for communicating with an external host 10ms after power-on-reset. Since the CC2538, CC13xx, and CC26xx ROM bootloader supports commands that can read the flash, it is also possible to disable the bootloader entirely for security reasons. The bootloader and backdoor functionality is configured in the CCA, CCFG.
Figure 2-1 shows as simplified flow chart for the CC13xx and CC26xx boot code. The flow is similar for CC2538 devices.