Cut and paste this URL to share the unmodified register and value:
https://regviz.com/r/Freescale Semiconductor/MK61F15WS/UART4/IR#0x0
IREN=0, TNP=00
UART Infrared Register
Transmitter narrow pulse
0 (00): 3/16.
1 (01): 1/16.
2 (10): 1/32.
3 (11): 1/4.
Infrared enable
0 (0): IR disabled.
1 (1): IR enabled.
no description available
https://github.com/cmsis-svd/cmsis-svd-data