DP83822I: without MCU

Brian Wang0928

Part Number: DP83822I
Other Parts Discussed in Thread: AMIC110

Is that possibly the DP83822I operation without MCU? In the system, there is no MCU in the system. We're wondering to know if it's possible to do the hardware setting on the DP83822 without register setting by MCU?

Used devices in the system

MAC:AMIC110

PHY: DP83822I (x2)

Regards

Brian

over 1 year ago

0 Gokul Koraganji over 1 year ago

TI__Mastermind 19250 points

Hi Brian,

I briefly went through the datasheet of AMIC110 and I see that it has MDC, MDIO pins. Any reason you don't want to use them?

Answering your question on whether DP83822 can be used without any register writes, I would say that it depends on the whole system and application. There are cases where PHY doesn't need any register programming.

--
Regards,
Gokul.

0 Wesley Chen over 1 year ago in reply to Gokul Koraganji

Prodigy 80 points

This system only uses ET1100 (EtherCAT ASIC) + DP83822I x 2pcs

0 Gokul Koraganji over 1 year ago in reply to Wesley Chen

TI__Mastermind 19250 points

Hi Wesley, Brian,

DP83822 can't be used without MDIO access for EtherCAT applications.

However, you can use DP83826 for EtherCAT applications without need for register access.

--
Regards,
Gokul.

0 Wesley Chen over 1 year ago in reply to Gokul Koraganji

Prodigy 80 points

Hi Gokul

We also have an EtherCAT product using the 83822. In addition to writing the 0x000A register to 0x0102, do we need to write other register values?

DP83822I: Link fail - Interface forum - Interface - TI E2E support forums

0 Gokul Koraganji over 1 year ago in reply to Wesley Chen

TI__Mastermind 19250 points

Hi Wesley,

Other than this 0x000A register, other configurations can be set through straps.

--
Regards,
Gokul.

0 Brian Wang0928 over 1 year ago in reply to Gokul Koraganji

TI__Genius 14030 points

Hello Gokul,

As DP83826 is suggested to use, we'd like to know what're the difference between DP83826 and DP83822 topologies and their performances?

is there performance comparison table between voltage and current type for EtherNET phy? Very thanks.

Regards

Brian

0 Gokul Koraganji over 1 year ago in reply to Brian Wang0928

TI__Mastermind 19250 points

Hi Brian,

Voltage and Current type transmitters will not have a large difference between their performance.

Current type transmitter consume higher current, with higher accuracy in Output differential voltage and impedance. Current type transmitters needs external 100 ohm differential impedance.

Voltage type transmitter consume lower current, with lower accuracy of Output different voltage compared to current type transmitter. This lower accuracy disadvantage is compensate by having a trim routine in the final test where the output differential voltage is trimmed to 1V.

So, effectively, you will not observe any performance different between these two type transmitters.

--
Regards,
Gokul.