SS1102C datasheet(51/129 Pages) ETC1

51 / 129 page

Direct Sequence Spread Spectrum Baseband Modem (SSTM)

PRELIMINARY V1.8

Figure 17.

Typical Communication Link Start-Up

The timing relationships between RTS_N and data exchange remain unchanged from

those of the full-duplex operation. RTS_N designates the direction of transmission. The

transmission is directed from a chip with RTS_N enabled to a chip with RTS_N

disabled. To change the direction of transmission the value of RTS_N should be

reversed. Note that, in the half-duplex mode, when RTS_N changes value the SSTM

resets itself. The transmitter stops transmission as soon as RTS_N is disabled. It is up to

the user to include and detect end-of-packet information so that invalid data is not

erroneously perceived as valid data. Finally, note that there is no provision for CSMA/

CD type avoidance in the hardware, it is up to the user or the modem system to

implement any desired collision avoidance schemes either in hardware and/or software.

A typical timing diagram for half-duplex operation is shown in Figure 18.

Acquisition

Burst

Acquisition

Burst

Empty

Burst

Master

Slave

Data

Burst

Empty

Burst

Data

Burst

Data

Burst

RLOCK

LOCKED

UWDET_N

Transmit

Receive

RLOCK

LOCKED

UWDET_N

SS1102C Datasheet(PDF) 51 Page - List of Unclassifed Manufacturers