DP83TC812R-Q1: DP83TC812 Master/Slave mode set

JB Z

I encountered a problem when using the DP83TC812 chip where I was unable to modify the master/slave mode. According to the chip manual, the master/slave mode can be set by modifying bit 14 of register address 0x1834.

However, in reality, the written value to this bit did not take effect. Moreover, after writing to this register, I read it back and found that the value remained the reset value instead of the one I wrote. Could you please help me look into this issue? Thank you.

6 months ago

0 Gregory Kobyakov 6 months ago

TI__Genius 9740 points

Hi JB,

The 0x1834 register is in the extended register space of the device. Therefore, to modify the register value, you must use the procedure defined in this FAQ.

Please note 0x1834 is in register space MMD1, as mentioned at the bottom of the linked FAQ.

Best regards,

Greg

0 JB Z 5 months ago in reply to Gregory Kobyakov

Prodigy 10 points

In my issue, I access this register follow table 7-17 already, the phenomenon is what I discribe in my issue.

0 Gregory Kobyakov 5 months ago in reply to JB Z

TI__Genius 9740 points

Hi JB,

Can you please share the script you use for writing/reading from register 0x1834?

Best regards,

Greg

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DP83TC812R-Q1: DP83TC812 Master/Slave mode set