SWRA466D February   2015  – August 2021 CC1310 , CC1310 , CC1352R , CC1352R , CC2538 , CC2538 , CC2620 , CC2620 , CC2630 , CC2630 , CC2640 , CC2640 , CC2640R2F , CC2640R2F , CC2640R2F-Q1 , CC2640R2F-Q1 , CC2642R , CC2642R , CC2642R-Q1 , CC2642R-Q1 , CC2650 , CC2650 , CC2650MODA , CC2650MODA , CC2652R , CC2652R , CC2652R7 , CC2652R7 , CC2652RB , CC2652RB , CC2652RSIP , CC2652RSIP

 

  1.   Trademarks
  2. 1Introduction
  3. 2ROM Bootloader
    1. 2.1 Configuring the Bootloader
      1. 2.1.1 CC2538
      2. 2.1.2 CC26x0
    2. 2.2 CC26x2
    3. 2.3 Communication Protocol
      1. 2.3.1 ACK/NACK
    4. 2.4 Interface Configuration
      1. 2.4.1 Hardware Pins
      2. 2.4.2 UART Configuration
      3. 2.4.3 Establishing Communication
      4. 2.4.4 Status Command
  4. 3Serial Bootloader Library (SBL)
    1. 3.1 SBL Return Values
    2. 3.2 SBL API
      1. 3.2.1 Device-Specific Functions
  5. 4Example Project
    1. 4.1 Hardware Setup
      1. 4.1.1 SmartRF06EB Virtual COM Port
        1. 4.1.1.1 External Serial Interface
      2. 4.1.2 LaunchPad Virtual COM Port
      3. 4.1.3 Bootloader Backdoor
    2. 4.2 Software Setup
      1. 4.2.1 Device Type
      2. 4.2.2 Baud Rate
    3. 4.3 Program Flow
      1. 4.3.1 Enumerate COM Ports
      2. 4.3.2 Create Device
      3. 4.3.3 Connect
      4. 4.3.4 Erase Flash Range
      5. 4.3.5 Write Flash Range
      6. 4.3.6 Calculate CRC32
      7. 4.3.7 Reset
  6. 5References
  7. 6Revision History

2.1.1 CC2538

The customer configuration area for CC2538 is called CCA and is placed in the uppermost flash sector, so the absolute address of the CCA depends on the device flash size. An 8-bit field in the CCA configures the bootloader backdoor functionality (byte offset 0x7D7). Table 2-1 lists the absolute address of this byte for different CC2538 variants.

Table 2-1 Address of 8-Bit Bootloader Configuration Field (CC2538 variants)
CC2538 VariantBootloader Configuration Address
Cx2538xF53 (512 KB flash)0x0027.FFD7
Cx2538xF23 (256 KB flash)0x0023.FFD7
Cx2538xF11 (128 KB flash)0x0021.FFD7

The structure of the bootloader configuration byte is shown in Table 2-2. The pins that can open the bootloader backdoor are PA0 - PA7. Select which pin to use by writing a value from 0 to 7 in the three least significant bits of the backdoor configuration byte.

Table 2-2 CC2538 Bootloader Backdoor Encoding
BitFieldValueDescriptionDefault
Value
7-5Reserved0Reserved. Should be all ones.111b
4EnabledEnable and disable backdoor function1
0Backdoor and bootloader disable
1Backdoor and bootloader enable
3LevelSets active level for selected pin on pad A1
0Active low
1Active high
2-0Pin numberThe number (0 - 7) of the pin on pad A that is used when backdoor is enable.111b (7)