Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Freescale Semiconductor/MK21D5WS/I2S0/RMR#0x0
RWM=0
SAI Receive Mask Register
Receive Word Mask
0 (0): Word N is enabled.
1 (1): Word N is masked.
no description available
https://github.com/cmsis-svd/cmsis-svd-data