HI,
I am trying to write to the data flash on a new battery design using the BQ20z65-R1 v1.05, but the aval software does not seem to be able to update the data flash. When I write to any of the registers they just turn red and revert to their original value. The SMBus communication works with all the SBS registers being read correctly.
I tried using bqChem and when that tries to write to the BQ20z65-R1 in order to update the chemistry, I get the following error: Writing Chemical Data, bqChemOCX - Fail read Verify, Abourt SubClass83 programming.
I can write to ManufacturerAccess, e.g. turn on the LEDs.
Flags/Status register summary:
BatteryStatus = TCA, TDA, INIT, DSG
OperationStatus = PRES, DSG, R_DIS
Do you know why I cannot write to the data flash?
Many thanks
Steve
Here are the reason why you wouldn't be able to update to data flash.
1) First, make sure the gauge is not in shutdown or sleep and SMBus communication is working.
2) If the device is sealed, reading and writing to flash is forbidden. Device must be unsealed first. If the SS or FAS bits in Operation Status, then the device is sealed.
3) Make sure there are no Permanent Failures. A PF prevents data flash writes. Data flash reads are still allowed.
4) Check the battery voltage. If it is lower than the Flash Update OK Voltage (located in Power class of data flash), then data flash writes are locked. Apply a charger voltage above the Flash Update OK Voltage to allow changing of this parameter to a lower voltage.
Hi
Thanks for your reply. Answers to your comments are below.
Chase 1) First, make sure the gauge is not in shutdown or sleep and SMBus communication is working. SMBUS Communication is working. 2) If the device is sealed, reading and writing to flash is forbidden. Device must be unsealed first. If the SS or FAS bits in Operation Status, then the device is sealed. SS and FAS are clear, it is a new device on a new PCB. 3) Make sure there are no Permanent Failures. A PF prevents data flash writes. Data flash reads are still allowed. The RSVD bit in PF status is set, all other bits are clear and PF in safety alert is clear 4) Check the battery voltage. If it is lower than the Flash Update OK Voltage (located in Power class of data flash), then data flash writes are locked. Apply a charger voltage above the Flash Update OK Voltage to allow changing of this parameter to a lower voltage. The battery voltage is reported as 11419mV, the Flash Update OK Voltage is 7500mV. It makes no difference if I apply a 16.8V charge voltage (it is a 4S core pack I have connected).
1) First, make sure the gauge is not in shutdown or sleep and SMBus communication is working. SMBUS Communication is working.
2) If the device is sealed, reading and writing to flash is forbidden. Device must be unsealed first. If the SS or FAS bits in Operation Status, then the device is sealed. SS and FAS are clear, it is a new device on a new PCB.
3) Make sure there are no Permanent Failures. A PF prevents data flash writes. Data flash reads are still allowed. The RSVD bit in PF status is set, all other bits are clear and PF in safety alert is clear
4) Check the battery voltage. If it is lower than the Flash Update OK Voltage (located in Power class of data flash), then data flash writes are locked. Apply a charger voltage above the Flash Update OK Voltage to allow changing of this parameter to a lower voltage. The battery voltage is reported as 11419mV, the Flash Update OK Voltage is 7500mV. It makes no difference if I apply a 16.8V charge voltage (it is a 4S core pack I have connected).
Below is a screen shot from the EVM software.
Below is a screen shot showing what happens when I try to write to the DF:
Many thanks for your help.
The RSVD bit that is set is what is causing your problems. Reset the gauge (send 0x0041 to command 0x00) and this will clear the RSVD but, thus allowing you to write to flash.
I've seen the above 'RSVD" pf status bit frequently on the BQ20Z90, what cause this bit to be set?
Not sure what causes it to be set, but I found out how to clear it!
The PFKey needs to be written to Manufacturer Access, see Permanent Fail Clear(PFKey) in the Tech Ref Manual.
Cheers