question about TLK10232 Loopback

hi Team,

I use TLK10232 to verify my 10G data path is ok or not, so I connect HSTXAP/N with HSRXAP/N with PRBS7 pattern (follow tlk10232_BringupProcedures_v2.pdf, "10G in 4:1 or 2:1 mode, Link Training, with 122.88 MHz Refclk , Data Rate =
9.8304Gbps" ), and it works because PRBS check correct. Now my question is if I conenct HSTXBP/N with HSRXAP/N on Hardware, that means I use Channel-A as PRBS7 source, and use Channel-B to verify, can it still work?

Thanks!
Simon

Hello Simon,

Please try this quick sequence:

ST ==> LOW
MODE_SEL ==> LOW
PRBSEN==> LOW
REFCLK_SEL==> LOW


Write 0x8610 to 0x1E.0000 //Reset the device
Write 0x0E10 to 0x1E.0000//Global Write Both Channels
Write 0x2000 to 0x07.0000 //Disable Autonegotiation
Write 0x0000 to 0x01.0096 // Disable Link Training

PRBSEN==>HIGH //Enable PRBS and Verifier in both channels
Check PRBS_PASS pin

With this procedure the device will be forced into 10GBASE-KR mode, disabling Autonegotiation and Link Training Features (Clause 73 Backplane), then the PRBS generator and verifiers are enabled through pin control and you can monitor thru PRBS_PASS pin if there are errors in the pattern.

I hope this helps. Please let me know your results.

Best Regards,
Luis

Hi Simon,

Sorry for the delayed response. Regarding the PRBSPASS, this pin depends of the PA[0], for channel A or B, since we are using both channels, in this case is not useful. So, you will need to force the device in 10GBASE-KR and use the PRBS31, and please try this procedure:

• Device Pin Settings
o Ensure ST input pin is Low
o Ensure MODE_SEL input pin is Low
o Ensure PRBSEN input pin is Low
o Ensure REFCLK_SEL input pin is Low
• Reset Device
o Issue a hard or soft reset (RESET_N asserted for at least 10 us -or- Write 1’b1 to 30.0.15)
Write 1'b1 to 30.0.11 GLOBAL_WRITE after device RESET.
• REFCLK input frequency and selection
o If using 156.25 MHz – Write 1’b0 to 30.29.12 (default)
o If using 312.5 MHz – Write 1’b1 to 30.29.12
o If REFCLK_0_P/N used – Write 1’b0 to 30.1.1 (default)
o If REFCLK_1_P/N used – Write 1’b1 to 30.1.1
• Default HS Tx settings loading and LT controls
o Write 16’h2000 to 7.0
o Write 16’h0000 to 30.150
o Write 16’h0008 to 30.14
o Write 16’h024D to 30.36864
o Write 16’h0004 to 30.33025
o Write 16’h0004 to 30.33024
o Write 16’h0000 to 30.33024
o Write 16’h0200 to 30.36865
o Write 16’h3000 to 7.0
o Write 16’h0002 to 30.150
o Write 16’h1C00 to 30.36869
• HS Serdes settings
o Write to 30.3, 30.4 (Refer to “tlk10232 Link Training Optimization Guide” for recommended values)
• Issue AN_RESTART
o Write 1’b1 to 7.0.9 AN_RESTART
• Wait for 1000ms
Device provisioning is complete at this point.

Enable KR HS test pattern generation
o Vendor Specific Test Patterns
231 – 1 PRBS / 223 – 1 PRBS / 27 – 1 PRBS – Write 1’b1 to 30.11.13
o KR Standard Test Patterns
231 – 1 PRBS pattern – enabled during test pattern select
Pseudo Random – Write 1’b1 to 3.42.3
Square Wave – Write 1’b1 to 3.42.3
• Enable KR HS test pattern verification
o Vendor Specific Test Patterns
231 – 1 PRBS / 223 – 1 PRBS / 27 – 1 PRBS – Write 1’b1 to 30.11.12
o KR Standard Test Patterns
231 – 1 PRBS – Write 1’b1 to 3.42.5 or Write 1’b1 to 30.11.12
Pseudo Random – Write 1’b1 to 3.42.2
Square Wave – Verification not supported
Clear Error Counters
o Vendor Specific Test Patterns
231 – 1 PRBS / 223 – 1 PRBS / 27 – 1 PRBS – Read 30.16 HS_ERROR_COUNTER to clear
o KR Standard Test Patterns
231 – 1 PRBS / Pseudo Random – Read 3.43 PCS_TP_ERR_COUNT to clear
Square Wave – Verification not supported
• Check Error Counters
o Vendor Specific Test Patterns
231 – 1 PRBS / 223 – 1 PRBS / 27 – 1 PRBS – Read Verify 30.16 HS_ERROR_COUNTER –
(16’h0000)
o KR Standard Test Patterns
231 – 1 PRBS / Pseudo Random – Read Verify 3.43 PCS_TP_ERR_COUNT – (16’h0000)
Square Wave – Verification not supported

I hope this helps.
Best Regards,
Luis