DP83826I: BASIC MODE

Hi Fujiwara,

Yasushi Fujiwara said:

Q1. Suppose you are using basic mode and pulled down to Strap0(pin#16)=low. If the IC starts up in this state, is it OK to recognize that it will work in Full-Duplex without changing the BMCR bit8 (Duplex Mode) in SMI?

Yes. The values of the strapped pins are sampled at power up. 

Yasushi Fujiwara said:

Q2. If device start up in Q1 condition, will the BMCR bit8 (Duplex Mode) follow Strap0 and enter "1"?

What do you mean by start up in Q1 condition? Do you mean if it starts up in the recommended power-up sequence in the datasheet? Yes that is correct.

Yasushi Fujiwara said:

Q3. If you are using Strap2(pin#30) and Strap1(pin#31) in basic mode and are using Strap1(pin#31) in the default state. If SMI changes BMCR's bit12 (Auto-Negotiation Enable) and bit13 (Speed Selection) after the IC is started in this state, is it OK to recognize that it can be forced to operate in 10Base-T.

Yes. The register write will overwrite the default state. 

Yasushi Fujiwara said:

Q4. If a hardware reset (pin#32) or BMCR bit15(Reset) is performed, does the IC start up with the value set by the Strap pin after each register value has been reset?

Yes. During hard reset, it is the same as power up. During software resets, the strap options are internally reloaded from the values sampled at power up or hard reset.

Best regards,

Melissa

Hi Fujiwara, 

If you are referring to Q1 in Q1  then the answer is yes

Best regards,

Melissa