TJA1128 Configuration Issue

[HariChitturi]

In one of our application, we are using TJA1128 SBC, configured SBC in Config mode and validated CRC, how to check the device is properly configured or not and the CRC which I have calculated is correct. I have written the calculated CRC to the MTPNV CRC register and after writing the CRC, I think the device will move to the standby mode, but from there when Iam trying to move to the normal mode it is not going to normal mode and LIN transceiver is not working.

The configuration registers are:

SYSTEM_REGISTER = 0x00u
WAKE_REGISTER = 0x10u
LDO_REGISTER = 0x00
LIN_REGISTER = 0x00u
WATCHDOG_REGISTER = 0x22u 
HVMPO_REGISTER = 0x00u 

and I am using the CRC algorithm provided in the datasheet:

I am getting the CRC as 0x26, is this correct (valid CRC)?

And I am also not moving to standby and normal mode. I want to know how to achieve this standby mode and normal mode.

* And one more thing I wanted to mention is that the SPI is also not reading and writing the registers after writing to the MTPNV CRC register.

[HariChitturi]

Hi Tomas,

I have gone through the Application hits of TJA1128. I have also checked the CRC, I am able to load the correct CRC to the MTPNV CRC register.

And I have checked for whether the device is moved to Standby mode or not, I have verified it by providing the watchdog trigger. Then I have made both EN and STBN pins HIGH to move to the port mode to check the device is properly configured or not. I have verified that the device is in port mode by checking the RX pin LOW. Later I have tried to move the normal mode to achieve the functionality of LIN transceiver by making EN pin HIGH and STBN pin LOW. I check for the Lin data, but it is not working, is there any other way to check that the device is in Normal mode. I have also tried moving to Goto sleep mode and checked the VCC output pin, but I am only getting HIGH signal on VCC. so, I need help with this Normal and Goto Sleep mode.

regards,

Hari

[TomasVaverka]

Hi Hari,

I would recommend you to take a closer look at our design resources available on the TJA1128 product website, mainly:

1. AH1801: Application Hints - TJA1128 LIN Mini System Basis Chip Family, especially Chapter 10. Software Flow

2. TJA1128 Software example

As for the CRC, there is the calculator available in the Documentation section as shown above.

Best regards,

Tomas