LDPC DOCSIS 3.1 Demo Example

Linux Drivers
Release Date
2023-07-22

This example demonstrates how to set up and control the BER test hardware and to configure a SD-FEC IP instance. It implements an interactive software described in the processor-based example design of SD-FEC Product Guide (PG256) .

Source path for the demo is located at: https://github.com/Xilinx/linux-examples/blob/master/sd-fec-1.1/sdfec-demo/files/main.c

To create images that can be deployed using an SD-CARD

  • Create petalinux project using the following command: 
$ petalinux-create -t project -s <xilinx-zcu111-v2019.2-final.bsp> -n plnx_sdfec_demo

Note: xilinx-zcu111-v2019.2-final.bsp is the PetaLinux BSP for ZCU111 Production Silicon Rev1.0 Board.

  • Change to the PetaLinux project directory using the following command: 
$ cd plnx_sdfec_demo
  • Build the Linux images using the following command: 
$ petalinux-build
  • After the above statement executes successfully, verify the images and the timestamp in the images directory in the PetaLinux project folder using the following commands: 
$ cd images/linux/ 
$ ls -al
  • Generate the Boot image using the following command: 
$ petalinux-package --boot --format BIN --fsbl zynqmp_fsbl.elf --u-boot --fpga system.bit

The above procedure will create the following SD-Card deployable images a. BOOT.bin b. image.ub

Copy the BOOT.BIN and image.ub from plnx-sdfec-demo/plnx_sdfec_demo/images/linux to a SD-CARD.

The following console log demonstrate how to run the SD-FEC demo, to exit the application press CTRL-C. 

root@xilinx-zcu111-zu28-es1-2018_3:~# sdfec-demo
Initialize all devices
metal: info:      metal_uio_dev_open: No IRQ for device a0000000.data_source_top.
metal: info:      metal_uio_dev_open: No IRQ for device a0030000.stats_top.
metal: info:      metal_uio_dev_open: No IRQ for device a0010000.monitor.
metal: info:      metal_uio_dev_open: No IRQ for device a0020000.monitor.
metal: info:      metal_uio_dev_open: No IRQ for device a00d0000.monitor.
metal: info:      metal_uio_dev_open: No IRQ for device a00e0000.monitor.
Open FECs
Setup LDPC code for decoder
Setup LDPC code for encoder
Start decoder FEC
Start encoder FEC
Setup data source, stats and monitors
Wait for finish
Collect stats
---- RESULTS ----
        Stats:
                Decode iteration count = 800
                Channel bit error count = 12079
                Channel block error count = 100
                Uncorrected bit error count after Decode = 13763
                Uncorrected block error count after Decode = 100
        Encoder Monitors:
                In Monitor First Timestamp = 2567215315
                In Monitor Last Timestamp = 2567216973
                In Monitor Num Stalled Clk Cycles = 965
                Out Monitor First Timestamp = 2567215410
                Out Monitor Last Timestamp =  2567217229
                Out Monitor Num Stalled Clk Cycles = 201
        Decoder Monitors:
                In Monitor First Timestamp = 2567215536
                In Monitor Last Timestamp = 2567229792
                In Monitor Num Stalled Clk Cycles = 3026
                Out Monitor First Timestamp = 2567215966
                Out Monitor Last Timestamp =  2567230706
                Out Monitor Num Stalled Clk Cycles = 863
Stop encoder FEC
Stop decoder FEC
Current config:
code        : 0
num_blocks  : 100
snr         : 6.000000
max_iter    : 8
term_on_pass: 0
mod_type    : 2
zero_data   : 0
skip_chan   : 0
New config? (y/n):y
Input new config:
code: 1
num_blocks: 100
snr:
Next config:
code        : 1
num_blocks  : 100
snr         : 6.000000
max_iter    : 8
term_on_pass: 0
mod_type    : 2
zero_data   : 0
skip_chan   : 0
Setup LDPC code for decoder
Setup LDPC code for encoder
Start decoder FEC
Start encoder FEC
Setup data source, stats and monitors
Wait for finish
Collect stats

---- RESULTS ----
        Stats:
                Decode iteration count = 800
                Channel bit error count = 73550
                Channel block error count = 100
                Uncorrected bit error count after Decode = 77466
                Uncorrected block error count after Decode = 100
        Encoder Monitors:
                In Monitor First Timestamp = 1521568905
                In Monitor Last Timestamp = 1521580327
                In Monitor Num Stalled Clk Cycles = 7462
                Out Monitor First Timestamp = 1521569258
                Out Monitor Last Timestamp =  1521580825
                Out Monitor Num Stalled Clk Cycles = 0
        Decoder Monitors:
                In Monitor First Timestamp = 1521569735
                In Monitor Last Timestamp = 1521661054
                In Monitor Num Stalled Clk Cycles = 40781
                Out Monitor First Timestamp = 1521571430
                Out Monitor Last Timestamp =  1521665176
                Out Monitor Num Stalled Clk Cycles = 0
Stop encoder FEC
Stop decoder FEC
Current config:
code        : 1
num_blocks  : 100
snr         : 6.000000
max_iter    : 8
term_on_pass: 0
mod_type    : 2
zero_data   : 0
skip_chan   : 0
New config? (y/n):