DP83867IR: How to set RGMII delay

Hi,

Procedure followed looks correct. 

a. Are you enabling Delay thru straps as well ?

b. Can you read 0x032, 0x86  before and after setting the delay ?

c. Which pins you are measuring the delay ?

Regards,
Geet

＞＞a. Are you enabling Delay thru straps as well ?
Are you talking about STRAP_RGMII_DIS?
The values ​​of STRAP_Sts are as follows.
0x006E = 0
0x006F = 0x3000

＞＞b. Can you read 0x032, 0x86  before and after setting the delay ?
Yes,I can.
Before and after : 0x0032 = 0x83 、0x0086 = 0x6d

＞＞c. Which pins you are measuring the delay ?
Only monitoring the setting value, not measuring.

Thank you.

Yoshida

HI,

"Only monitoring the setting value, not measuring"

But in your original post, you mention you don't see the delay in signal...  Ok. How you are concluding the delay is not applied ? What values you are programming ?

Regards,
Geet

Hi Geet,

Actually, we did not see the signal, sorry to confuse you.

The problem is that after writing the date to RGMIIDCTL register then read it but the value is not updated. The write and read works fine for other resister.

Do you have any idea why the value to RGMIIDCTL is not updated?

Regards,

Uchikoshi

Here is additional information.

After reset, when reading RGMIIDCTL shows 0x6d. It is not always 0x6d but it is not the initial value as 0x77 so we are assuming this delay is controlled by hardware. Is this strange behavior that the initial value is not 0x77?

The value which we attempt to write is 0xA8 but as we posted in previous post, it is not updated.

Regards,

Uchikoshi

Hi,

RGMIICTRL shall have delay mode enabled to change the delays in RGMIIDCTL.

Regards,

Geet

Your answer is NOT to our questions.

After setting RGMIICTL, change RGMIIDCTL but not updated. Please read our post again.

Regards,

Uchikoshi

HI Uchikoshi-san,

As I mentioned in my original response, your sequence looks correct.  

Regards,

Geet

Hi Geet,

Thank you for your reply.

Can I have your comment to below behavior?

>After reset, when reading RGMIIDCTL shows 0x6d. It is not always 0x6d but it is not the initial value as 0x77 so we are assuming this delay is controlled by hardware. Is this strange behavior that the initial value is not 0x77?

Regards,

Uchikoshi

Hi,

What's the value of 0x0032 at reset ? bit 0 and bit 1 are set to "1" ?

Regards,
Geet