Method and apparatus for automatic detection and healing of signal pair crossover on a high performance serial bus
View Patent ↗An automatic crossover and healing process is disclosed for the P1394b standard. In particular, a crossover process is disclosed which comprises coupling the transmitting logic of a PHY to TPA, and coupling the receive logic of a PHY to TPB.
1. A computer program product containing instructions which, when executed by a computer, automatically detect and heal a crossover in a data communications system having a P1394b-compliant bus and a PHY which wishes to join the bus, by:
determining, by the PHY, whether it has received a tone;
if the PHY has not received a tone, then examining a random Boolean value; and
if the value of said random Boolean value is true, then implementing, by said PHY, a crossover process.
2. The computer program product of claim 1 , wherein said crossover process comprises instructions, which, when executed by a computer, couple transmitting logic of said PHY to TPA, and couple receive logic of said PHY to TPB.
3. The computer program product of claim 2 , where said system is operatively coupled with a non-crossover cable.
4. A computer program product containing instructions, which, when executed by a computer, automatically detect and heal a crossover in a data communications system having a P1394b-compliant bus and a PHY which wishes to join the bus, by:
determining, by the PHY, whether it has received a tone;
if the PHY has not received a tone, then examining a random Boolean value;
if the value of said random Boolean value is true, determining, by said PHY, whether said PHY is sending a tone;
if said PHY is sending a tone, then waiting a predetermined period of time;
further determining by said PHY if said PHY has received a tone; and
if said PHY has not received a tone, then implementing, by said PHY, a crossover process.
5. The computer program product of claim 4 , wherein said crossover process comprises instructions which, when executed by a computer, couple transmitting logic of said PHY to TPA, and couple receive logic of said PHY to TPB.
6. The computer program product of claim 5 , where said system is operatively coupled with a non-crossover cable.