SLUUB65B May 2015 – December 2022
The contents in the DF are protected by three checksum parameters:
Each of these checksums is a 16-bit unsigned integer sum of each byte in the data flash. The sum is calculated on a byte-by-byte basis. The most significant bit of the checksum is masked yielding a 15-bit checksum. This checksum is compared with the value generated by the command 0x1A. The checksum execution takes approximately 5 ms and during this time, the fuel gauge does not communicate.
For each of the above checksums, certain data flash locations are excluded in the calculation of the checksum.
Table 14-1 shows the data flash locations that are excluded for the All Data Flash Checksum computation.
Class | Subclass ID | Subclass | Comment |
---|---|---|---|
Configuration | 56 | Manufacturer Data | Pack Lot Code, PCB Lot Code |
Configuration | 57 | Integrity Data | Reset Counter – Full (private) Reset Counter – Watchdog (private) |
Configuration | 57 | Integrity Data | All DF Checksum |
System Data | 58 | Manufacturer Info | Block A Block B |
Calibration | 104 | Data | CC Gain CC Delta CC Offset Board offset Int Temp Offset Ext Temp Offset Pack V offset |
Table 14-2 shows the data flash locations that are included for the Static Chem Data Flash Checksum computation.
Class | Subclass ID | Subclass | Comment |
---|---|---|---|
OCV Table | 83 | OCV Table | ChemID (public) OCVa Table (private) |
OCVb Table | 84 | OCVb Table | OCVb Table (private) |
Rb_Hi Table | 85 | Rb_Hi Table | Rb Hi Table (private) |
Rb_Lo Table | 108 | Rb_Lo Table | Rb Lo Table (private) |
Gas Gauging | 80 | IT Cfg | Q Invalid Max V Q Invalid Min V |
Table 14-3 shows the data flash locations that are excluded for the Static Data Flash Checksum computation.
Class | Subclass ID | Subclass | Comment |
---|---|---|---|
Configuration | 48 | Data | Cycle Count |
Configuration | 56 | Manufacturer Data | Pack Lot Code, PCB Lot Code |
Configuration | 57 | Integrity Data | Reset Counter – Full (private) Reset Counter – Watchdog (private) |
Configuration | 57 | Integrity Data | All DF Checksum |
Configuration | 57 | Integrity Data | Static DF Checksum |
System Data | 58 | Manufacturer Info | Block A Block B |
LT Data | 59 | Lifetime Data | All Lifetime Data |
LT Data | 59 | Lifetime Temp Samples | All Lifetime Temp Samples |
Gas Gauging | 82 | State | Qmax Cell 0 Cycle Count Update_Status V at Chg Term Avg I Last Run Avg P Last Run Delta Voltage |
Ra Tables | 88 | Data | Ra Table |
Ra Tables | 89 | Data | Rax Table |
Calibration | 104 | Data | CC Gain CC Delta CC Offset Board offset Int Temp Offset Ext Temp Offset Pack V offset |
Subclass ID | Subclass | Offset | Name | Data Type | Value | Unit | ||
---|---|---|---|---|---|---|---|---|
Min | Max | Default | ||||||
57 | Integrity Data | 6 | All DF Checksum | H2 | 0x00 | 0x7FFF | 0x00 | Number |
Integrity Data | 8 | Static Chem DF Checksum | H2 | 0x00 | 0x7FFF | 0x7C23 | Number | |
Integrity Data | 10 | Static DF Checksum | H2 | 0x00 | 0x7FFF | 0x00 | Number |