Both of these methods "Skip start bit" and "disable skip start bit" are suggested only when the UART is used as a wake up source. Not otherwise.
So there are two things you can do here:
1. Use UART as a wake up source. Depending on your data rate, you can choose between the two methods suggested in the datasheet
2. If you are not using UART as wake up source, you shouldn't send data to the UART RX unless the device has woken up. For which you can signal the other device that the device has woken up using the Tx pin and then receive the data.
Hope this helps!
Thanks for you reply.
I am using both UART and Timer as my wake up source. If I choose "skip start", dummy data is received when timer wake up the deepsleep. And I will need to add preamble data if I disable the "skip start" feature. This is my question.
Thanks for the update. It is recommended to use 0x00 as the preamble byte for your application.
So when the device wakes up due to timer, PSoC will read even the preamble data. In such cases, you need to discard the packet when the data is 0x00. Do you face any difficulties in this? Please let us know.