SBC UJA113X CAN FD settings not possible

[shilhas]

Hi

We are using SBC UJA113xFD for our CAN tranceiver. We intend to use it for CAN FD communication with baudrate 500/2000 Kbps for protocol and FD parts respectively. 

I am trying to set the registers:

1. CAN partial N/W configuration register (26H) = 0x05 (500 Kbps)
2. Frame control register (address 2FH) = 0x88
3. and CAN control register (20H) = 0x46H (CAN FD tolerance = enabled and CAN trcv = Active)

But this settings do not take effect. When the request for reg (20H) = 0x46 is sent register is set to 0x06. Above settings I have tried even in standby and normal SBC modes. I have also checked lock control and interrupt status register, there is no issue there.

Any support to resolve the issue is highly appreciated.

exact device ID is UJA11323V

Thanks

SR

[guoweisun]

can you read the register-22h value?

[shilhas]

?

[shilhas]

yes it returns 0x88 when register 20H = 0x06 (active mode), and sometimes 0x80H

[guoweisun]

You selection SBC part number is UJA1132HW/3V3,right?

[shilhas]

In Forced normal mode CAN FD communication work

[guoweisun]

Since it can work,what's your issue now?

[shilhas]

It is forced Normal mode where you cannot set any of the registers. This is not the mode in which you want to use your SBC.

??

[guoweisun]

You mean only can enter into forced normal mode and can't enter into normal mode/sleep mode/standby mode?

[shilhas]

No.

What I mean is when the SBC was in FORCED normal mode CAN commuincation was working. Now I have programmed NV memory of SBC to put SBC in SW development mode. I have initiallized SBC and put it in NORMAL mode and CAN tranciever in active mode, and now I expect that CAN communication should work. But it does not, So I thought probably I need to set the CFDC bit so I tried to set it and I am not able to set it. Probably the HW does not support the CFDC bit. But then why doesn't the CAN comuincation work.

[shilhas]

Yes

[shilhas]

Please also note that register setting for register 26H and 2FH also does not work. It is unchanged after write request. My SBC is in SW development mode. I am able to set it to NORMAL mode or standby mode. SBC watch dog is in autonomous mode and it is OFF.