Design Considerations for Host and NCP Communications#

Silicon Labs recommends these best practices for Host and NCP communications:

• Use a well-tuned crystal (38.4 MHz) for any wireless mesh application.

• Use of RTS/CTS hardware flow control is highly recommended. It will aid in electrically-noisy environments.

• UART-based NCP is not suitable for low-power designs due to the inability of the NCP to enter into any sleep modes. In designs where low power NCPs are required, Silicon Labs recommends using SPI-NCP instead. For more information, refer to SPI Host Interfacing Guide for Zigbee.

• Silicon Labs recommends including the nRESET and Bootload pins in all Host-NCP hardware designs as a backup for situations where serial communication are lost between the Host and NCP. For secure designs (utilizing secure EZSP) or security products, these connections should be considered mandatory.