SNLS742A September 2023 – April 2024 DP83TC811-Q1
PRODUCTION DATA
Time domain reflectometry helps determine the quality of the cable, connectors and terminations in addition to estimating OPEN and SHORT faults along a cable. The DP83TC811-Q1 transmits a test pulse down the attached twisted-pair cable. Transmitted pulses continue down the cable and reflect from each imperfection and fault, allowing the device to measure the time to return and strength (amplitude) of all reflections. This technique enables the DP83TC811-Q1 to identify cable OPENs and SHORTs.
TDR is activated by setting bit[15] in the Section 7.6.19. Cable diagnostic status is obtained by reading bits[1:0] in the TDR register. TDR runs are stored in the Section 7.6.22. When more than one fault is present, additional locations are identified by the Section 7.6.23 and the Section 7.6.25.