TLK10031: TLK10031_LINK_ISSUES

hi, see my inputs below.

1. In order to get link is it enough to supply power and clk ? Or should I configure the tlk10031 with specific configuration?
2. I configured the TLK as follows:
   1. PDTRXA_N = '1'
   2. RESET_N = '1'
   3. TEST_EN = '0'
   4. PRBSEN = '0'
   5. ST = '0'
   6. MODE_SEL = '0'
   7. REFCLK = 156.25

3. What should be the correct configuration in order to get link?
4. I am using SFP+ optical module in what mode should I be working(10G,10GBASE_KR)?

• For SFP+ host interface cases,
  • you should set the TLK10031 to 10GBASE-KR mode with link training and auto-negotiation disabled.
  • KR mode is default mode for this transceiver. You may refer to the datasheet for the register bits to disable link training and auto-negotiation
  • SerDes multipliers would need to be set for 10.3125Gbps HS with 156.25MHz reference clock
  • 
• As it relates to control pins,
  • I would recommend to set mode_sel=0, since we want to disable auto-negotiation for optical case.
  • Once MODE_SEL=1 then ST is a don't care
  • 
  • TEST-EN=0 and PRBSEN=0 is correct
  • For RESET_N we recommend to hold it low during power up and then setting it high after initialization. But simply pulling it high should be ok
  • 
  • PDTTXA_N=1 is correct

3. In data sheet table 7-2 ("operating mode selection) lines 2,3 is in with contradiction to what is written in register 0x0001 DA:0X1E which of them is the correct one?
   • See my input above. I would recommend to MODE_SEL=1 for optical mode since auto-negotiation is not used for this case. Alternatively if MODE_SEL=0 then you need to set 1E.0001 bit 10 to 1 to fix the data rate to 10G

Thanks,

Rodrigo Natal

Please provide feedback related to my latest response. I believe it addresses the configuration questions you have raised.

Thanks,

Rodrigo