# Regular Meeting (2020.2.24) ## Completed * Testing ibert-GTY * Hough Transform for curve detect (opencv+python) ## Ibert * Using example files * Transrate: **25Gbps x 4ch** * Fiber loop-back ![opt-modules](https://i.imgur.com/mH37m5q.jpg) * Result ![I-bert-result](https://i.imgur.com/2XMCTzA.png) * ibert-test without encoding with 8B/10B or 64B/66B ... etc. ![arch-GTY](https://i.imgur.com/83AQ2Em.png) * What's the ibert (LFSR)? ![lfsr-gif](https://i.pinimg.com/originals/cf/3d/02/cf3d02eac2e6b573a9025fe6e5550836.gif) * Both (LFSR + Scrambler) and 8B/10 provide DC-Balance * LFSR detected error is not directly * if we sent random data, how to detect error in receiver * LFSR without control code * Why we need DC-Balance in Hi-Speed transmission circuit ![DC-bal-ac-couple](https://i.imgur.com/LXCNqcM.png) ![DC-bal-8b-10b](https://i.imgur.com/Fj0V1FB.png) * Some probles * I can't specify ref-clk (refclk-0, refclk-1) if I use ibert-IP * UT-3 board layout refclk-0, refclk-1 to same clock, maybe UT-4 is the same. ![gty-clks-0](https://i.imgur.com/W1jHAYw.png) ![gty-clks-1](https://i.imgur.com/jds4KmJ.png) ![gty-clks-ibert]() ## Hough Transform for curve detect * Compare equtions * Hough transform for strength line ![](https://i.imgur.com/0DpopdT.png) * Hough transform for curve ![](https://i.imgur.com/zwFBNyY.png) Threashole = 30 * Hough transform for curve ![](https://i.imgur.com/QC6zAsd.jpg) ![](https://i.imgur.com/HrijxW1.jpg) * Hough transform for strength line ![](https://i.imgur.com/tLTbsAD.jpg) ###### tags: `Regular Meeting` `DeWei`