SLUAAP5 july   2023 UCD3138 , UCD3138064 , UCD3138064A , UCD3138128 , UCD3138128A , UCD3138A , UCD3138A64

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Why Lockup Can Occur
  5. 2Reasons for Lockup
    1. 2.1 Wrong Code in the load.asm
    2. 2.2 Misoperation with TI GUI
    3. 2.3 zero_out_integrity_word Function Fails
    4. 2.4 PMBus Communication Fails
    5. 2.5 Unexpected Occurrences
  6. 3How to Avoid a Lockup
  7. 4Unlock with JTAG
    1. 4.1 Enable JTAG Functionality
    2. 4.2 New Target Configuration in CCS
    3. 4.3 Clear the Flash
  8. 5Summary
  9. 6References

3 How to Avoid a Lockup

To avoid a lockup, follow the three steps:

Step 1: DO NOT write checksum when programming a UCD device if there is a possibility the firmware is not working. While checksum can still jump to pflash for execution after programming, a UCD device can always get back to ROM on reset. Follow the configurations in Figure 3-1.

GUID-20230602-SS0I-6VQF-XNHP-NKZGDSKGC3XH-low.png Figure 3-1 Programming Without Checksum

Step 2: Confirm the expected location of checksum is cleared correctly. Click on the command Command Program to jump to ROM (Send Byte 0xD9 to address xx) to send UCD back to ROM mode.

GUID-20230602-SS0I-PQZQ-K8CV-FMNLL4RXVRBM-low.png Figure 3-2 Jumping to ROM Mode

Step 3: Go to the Checksums tag. Select the Dump button to read each of the checksums by configuring the Block configuration. Check whether the expected location of checksum is cleared. If cleared correctly, the field shows all zeros.

GUID-20230602-SS0I-DMPZ-HZSJ-020HHWDDZWCL-low.png Figure 3-3 Verification on Checksum Value

Check code to confirm the correct checksum is cleared. Once cleared as expected, program UCD device with checksum.