Component Feature

• 8GB eMCP eMMC
• Controller :
• Hy

Failure Symptom

• Using Packed Command while SPO (sudden power off ) caused data disappeared

Failure procedure

1. Normal Case
   • At first picture, issue packed command
   • At second picture, write data seperately
2. Crash Case
   • At first picture, power-off at command 7
   • At second picture, command 6 got no data

Cause

• Normal Case
  • First, Packed Data is written to SRAM, not to NAND
  • If same address data comes in, merging will be done with existing same address data at SRAM
  • and then, written to NAND
• Crash Case
  • First, Packed Data is written to SRAM, not to NAND
  • The addresses of 5th and 7th data is same, and then, the two data is merged at SRAM
  • and then while written to NAND, SPO(sudden power off ) occured
  • the 6th data was not written to NAND