DP83848C: Half Duplex Mode

Himanshu Batra

Prodigy 120 points

Part Number: DP83848C

I am using TI’s Ethernet PHY DP83848CVV with ST microcontroller. PHY is working fine with following cases

100Mbps + Full Duplex Mode + Auto Negotiation Disable
10Mbps + Full Duplex Mode + Auto Negotiation Disable.

For clarification here I am attaching snapshot of PHY circuit diagram.

But when we changed its duplex mode from Full to Half Duplex mode it stops working.

Kindly suggest, how we can solve this problem.

over 7 years ago

0 Geet Modi over 7 years ago

TI__Mastermind 26320 points

Hi Himanshu,

When you say, it stops working ?

a. Phy is not linking up or
b. Phy is linking but no data transfer is happening ?

Regards,
Geet

0 Himanshu Batra over 7 years ago in reply to Geet Modi

Prodigy 120 points

Hi Geet,

Phy is linking up but no data transfer is happening

Regards,
Himanshu

0 Geet Modi over 7 years ago in reply to Himanshu Batra

TI__Mastermind 26320 points

Thanks. Can you check which direction you have having issues ? Transmit or Recieve ?

For Half Duplex, COL and CRS are also needed to be interfaced with MAC. Have you connected them ?

Regards,
Geet

0 Himanshu Batra over 7 years ago in reply to Geet Modi

Prodigy 120 points

Hi Geet,
Thanks for your valuable advice. COL and CRS were not connected in our schematic. After connecting them it started working.

Regards,
Himanshu

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DP83848C: Half Duplex Mode