Collision Detection Function - Samsung KS8910 User Manual

10BASE-T DIGITAL BLOCKS

COLLISION DETECTION FUNCTION

The collision detection function operates on the twisted-pair side of the interface. A collision is defined as the simul-
taneous presence of valid signals on both the TPI circuit and the TPO circuit. The 10BASE-T transceiver reports
collisions to the back-end via the COL pin. If the TPI circuit becomes active while there is activity on the TPO circuit,
the TPI data is passed to the back-end over the RXD circuit, disabling normal loopback. Figure 5-3 is a state dia-
gram of the 10BASE-T transceiver collision detection function.
CI
(collision Input)
CID_S1_1w
CID_S1
CI=' 0 '
CID_S1O_1w
5-4
CID_IDLE
CI=' 1 '
CI=' 1 '
CI=' 0 '
CID_S1O
cid_Col=' 0 '
' ( collision detec)
Figure 5-3. State Diagram of Collision Detection Function
KS8910 100/10 Mbps ETHERNET TRANSCEIVER
Collision State
Machine
Reset or
default
CID_IDLE_w
cid_Col=' 0 '
CI=' 1 '
cid_Col=' 0 '
CID_S1O1_1w
cid_COL
(collision detected)
CI=' 0 '
CID_SO1O
CID_SO1O_1w
CI=' 1 '
CI=' 0 '
CID_S1O1
CI=' 1 '
Preliminary Spec. ver
1.4