Hi vap,
> BTW, it is another problem because bit rate error is particularly high with this bit rate.
There is a note near Table 14.4 in RZ/A1H Group User's Manual: Hardware.
"The bit rate error should be less than or equal to 1%."
To reduce the bit rate error,
(1) Modify sh-sci.c driver to support BGDM and/or ABCS bits of SCEMR register.
This can increase the number of selectable frequency and "might" solve your bit rate error problem.
(2) Use external clock from SCK pin.
Modify your RZ/A1H board and sh-sci.c driver to support external clock from SCK pin.
This can solve your bit rate error problem completely.
regards,