Renesas R-IN32M3 Series User Manual page 162

R-IN32M3-EC User's Manual
The operation of TDR function is performed by using register 25 and register 26 as follows.
Disable the auto-negotiation and auto-crossover and set to 100Base-Half Duplex at first, otherwise measuring cannot be
performed correctly. Then, set the register with parameters relating to transmission pulse and pulse detection whether the
TX line or RX line is measured. Pulse is sent by writing 1 to the DIAG_INIT bit and the measurement is started after the
configuration is complete. When the measurement is completed, the DIAG_DONE bit is set to 1. The value of counter
when pulse is detected is saved in the DIAGCNT register and the information about open or short is saved in the
DIAG_POL register at this time.
The following shows an example of setting the parameters when measuring. However, it is necessary to adjust some
parameters depending on the configuration of hardware and the installation environment.
No. Cable Length
1 Below 20m
2 20m to 40m
3 40m to 60m
4 60m to 80m
5 More than 80m
R18UZ0003EJ0501
Jan. 12, 2021
ADC_TRIGGER CNT_WINDOW
10
10
8
8
8
PW_DIAG
15 2
30 8
50 8
60 12
75 12
7. Ethernet PHY Function
Conditions of Counter Value
DIAGCNT  255 and
DIAGCNT  42
DIAGCNT  255 and
32  DIAGCNT  68
DIAGCNT  255 and
56  DIAGCNT  88
DIAGCNT  255 and
78  DIAGCNT  114
DIAGCNT  255 and
106  DIAGCNT
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