GMSK Packet Data Modem
CMX909B
calculate and add the CRC bits as required, encode the result with Forward Error Correction coding,
interleave then scramble the bits before transmission.
In receive mode, the modem can be instructed to assemble a block’s worth of received bits, de-
scramble and de-interleave the bits, check and correct them (using the FEC coding) and check the
resulting CRC before placing the received binary data into the Data Buffer for the µC to read.
The modem can also handle the transmission and reception of unformatted data, to allow the
transmission of special Bit and Frame Synchronisation sequences or test patterns.
ã 2001 Consumer Microcircuits Limited
11
D/909B/1
CMLMICRO [ CML MICROCIRCUITS ]
