CCS/AWR1642BOOST: CCS/AWR1642BOOST: Qustion about DCAN Bit rate

Tool/software: Code Composer Studio

Hi TI,

I got some question with AWR1642 DCAN bit rate as below:

I use  sample code main.c by path  mmwave_sdk_02_00_00_04\packages\ti\drivers\can\test\common.

Use parameter DCAN_APP_BIT_RATE 1000000U/500000U/250000U. It's can communicate with pcan-viewer successfully. when i adjust Norminal Bit rate selection.

but when I modify parameter DCAN_APP_BIT_RATE  to 800000U, It's can not communicate with pcan-viewer. 

Here is my source code define:

pcan-viewer setup :

why sample code can use 1 MBit/s,500 kBit/s,250 kBit/s but not 800 kBit/s.

How do i use 800 kBit/s by fix somthing.

please assistance 

thanks.