Part Number: DP83822I
Because of a non-standard ethernet connector our device shows some problems while EMC testing and certification. We can measure high radiation between 40 and 60 MHz in 100Base-TX mode.
In the datasheet we found the register 0x0403 - Line Driver Control Register (LDCTRL) to modify the voltage swing. So we read out the register with phytool:
phytool read eth0/1/0x0403
0xA240 => curiously these are not the default values
Then we want to set the "100Base-TX Line Driver Swing" (bit 7:4) to 0000:
phytool write eth0/1/0x0403 0xA200
But when we read out the register again, it is still 0xA240. What are we doing wrong?
Is there any other chance to reduce the radiation by software?
