Patent ID: 6169773
Filing Date: 2001-01-02
Classification: H04L

Abstract:
A device for synchronizing a block counter in a Radio Data System (RDS) receiver, the RDS receiver including a program-controlled decoder, the device comprising: a buffer memory receiving bits of a data block and serially storing the received bits of the data block; a bit counter counting a number of the received bits, wherein, during a last bit period of the data block being stored, data is retrieved at least twice from the buffer memory as retrieved bits; a first XOR stage serially linking the retrieved bits with further bits of an offset data word and generating XOR bits, the offset data word being generated in the program controlled decoder by an offset word generator, the offset word generator including an address counter, the address counter causing a generation of a next offset data word when an incrementing pulse is received by the address counter; a syndrome register calculating a syndrome value and receiving the XOR bits in a first readout operation via an inhibition stage; a second XOR stage coupled to an output of the first XOR stage, the second XOR stage receiving the XOR bits and being capable of performing an error correction operation in a second readout operation; a first program-controlled arrangement reading the buffer memory at most 2 n times in each bit period, wherein n is equal to a number of allowable offset data words; a second arrangement differentiating odd-numbered readout cycles from even-numbered readout cycles; a third arrangement coupled to the syndrome register, the third arrangement providing a synchronizing signal when the syndrome value generated by the syndrome register equals zero, wherein, after the synchronizing signal is provided, the third arrangement sets the bit counter to zero and a block counter to a status of the address counter; and a fourth arrangement inhibiting an incrementing input of the address counter and an input of the syndrome register at each of the even-numbered readout cycles.