• State
  • Locked Locked
  • Replies 2 replies
  • Subscribers 64 subscribers
  • Views 481 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

EV2300 checksum method

Mike_chute
Intellectual 825 points
Other Parts Discussed in Thread: BQ27501

We are planning to send data to the pack during testing. How do you calculate the check sum? I have captured the smb communication and know the value of the checksum for the commands sent by the EV2300.

  • 0
    TI__Expert 3865 points

    Attached is a document regarding SMBus in gas gauge devices.

    PEC is calculated using CRC-8. The document has a section on PEC, as well as showing reader where to find more information in the internet.

    SMBus made simple_v5.pdf
  • 0 in reply to Jackie Hui
    Prodigy 10 points

    Hi, Jackie,

             I want to program BQ27501 at ATE tester. But I have a trouble to get the checksum as below show from Dffs file. Below is section of Dffs file. From datasheet, we need wait around 45mS time to get checksum. Below is our command to device BQ27501. Where should be add the wait time?

    Start ----- write 0x16 ----- got Acknowledge from slaver------ write 004 ----- got Acknowledge from slaver ------ >Restart -----write 0x17 (set to read) ------- got acknowledge -------- got data 0x24 ----- + ACKnowledge ------ got data 0xAA ----- + ACKnowledge ------- got 0x3A -----  ACKnowledge ------- got 0xF4 ----- NO ACK

             My question is ,where shold be add wait time to get read checksum? Could you give you help for this? Thank you in advance.

    Sample line from Dffs file:
    C: 16 04 24 AA 3A F4
    W: 16 00 0F
    W: 16 64 0F 00
    X: 4000

    Best regards

    Alan