CC1021.Need to understand how to separate the Data from the Preamble.please reply ASAP

[[email protected]]

I have a demo board which comprises of a Chipcon CC1021 chip connected
to a Microcontroller.Reading thru the Datasheets of CC1021 i
understand that the CC1021 can be used to Modulate data in either
NRZ,Manchester Encoded or Transparent Async UART format.Now apart from
all this we need to have a Preamble for all data packets which is just
a sequence of 1s and 0s and this is not encoded in any of the
formats(NRZ,Manchester Encoded or Transparent Async UART).
Is there a way to isolate the Preamble from the data.If so how?

 

[Robert Lacoste]

I have a demo board which comprises of a Chipcon CC1021 chip connected
to a Microcontroller.Reading thru the Datasheets of CC1021 i
understand that the CC1021 can be used to Modulate data in either
NRZ,Manchester Encoded or Transparent Async UART format.Now apart from
all this we need to have a Preamble for all data packets which is just
a sequence of 1s and 0s and this is not encoded in any of the
formats(NRZ,Manchester Encoded or Transparent Async UART).
Is there a way to isolate the Preamble from the data.If so how?

Hi Arun,
With "basic logic" transceivers like the CC1021 it is you job, I mean the
managment of preambles, synchronization bytes, data framing, checksums, etc
should be done by the microcontroller in charge of the CC1021. You will find
application notes on Texas's web site with code examples running on their
demo board. As you've stated on the logic side the only processing that
could be done by the RF chip is NRZ/Manchester encoding & decoding, nothing
more.
Alternatively, if a slightly lower sensitivity is ok for you application,
you can have a look at newer chips like the CC1101/CC1100 which allows a
full hardware management of preamples and framing.
Yours,
Robert Lacoste
ALCIOM - The mixed signal experts
www.alciom.com