What is the difference between EZSP UART and EZSP SPI on the EM260?

The short answer to this question is that EZSP SPI is designed with the embedded application in mind, whereas EZSP UART (or ASH) is designed for use with a bigger host, possibly a PC, running a complicated operating system which may not be able to respond to the EM260 in a timely fashion. However, in some cases, this rule may be broken, if the developer understands the details of the differences between these two protocols. Here are the details:

· EZSP UART does not support sleep

· EZSP UART requires more RAM/Flash on the host

· EZSP UART runs at 115.2 kbps, which means it may impact overall throughput of the radio.

· EZSP UART includes tolerance of host scheduling delays, data loss, and corruption