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Ubuntu conversion from Desktop to Server

Source: https://www.technomancer.com/archives/789

# Do this as a root
# Install Ubuntu Server, after stopping unattended upgrades
systemctl disable unattended-upgrades
systemctl set-default multi-user.target
apt update && apt -y upgrade 

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ASAHIネットのDS-Liteの終端(AFTR)を取得する

ASAHIネットがDS-Lite対応したので、 自宅の適当なLinuxルーターにて設定しようとして詰まったAFTR取得に関するメモ。

Linuxルーターを使ってる人向けのニッチなものだけど、情報として残しておく。

終端の情報公開について

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• Gstreamer Pipeline Samples
  • Video
    • display test video
    • record to file
    • record and display at the same time(queue)
    • record webcam to *.mp4(jetson nano)
    • fps test
  • Audio
  • Mux Video and Audio
• Media File

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Installing TeXLive on Ubuntu

For Ubuntu 22.04.4 LTS and TeXLive 2024

Don't

• Do not use default given packages. They are too old and obsolete.

Remove installed packages by apt first

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ACHANNELS 1
# SCU-17 PCM CODEM device: check with `aplay -l`
ADEVICE plughw:1,0

# This serial device name is for SCU-17. Use `if01-port0` for the PTT control of the data port with RTS.
PTT /dev/serial/by-id/usb-Silicon_Labs_CP2105_Dual_USB_to_UART_Bridge_Controller_devicename-if01-port0 RTS

CHANNEL 0

MYCALL yourcall-SSID

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Do not enable QUIC on 1280-byte MTU IPv6 networks

Synopsis

• QUIC requires transmission of at least 1350 bytes of UDP packets on IPv6 (and 1370 bytes on IPv4).
• On Chrome/Chromium (and Vivaldi), if sending 1350-byte UDP packet fails on IPv6, fallback to HTTP/2 over TCP immediately occurs.

Implementation details on Chrome/Chromium (60.0.3112.55 on Vivaldi)

See the explanation in Japanese for the further details on the current implementation. Note well that this differs from the latest version of QUIC Internet-Draft: see draft-ietf-quic-transport-01 Section 8. Quote:

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while true; do date; sleep 5; done

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ATECC608A I2C Notes

Here be dragons

WARNING: AS THE DEVICE CAN BE CONFIGURED ONLY ONCE, PLEASE BE WARNED THAT YOU MIGHT EASILY BRICK THE CHIP! USE AT YOUR OWN RISK!

Circuit

Please make sure to use proper circuit for ATECC608A with pullups and decoupling capacitors when hooked to a MCU. A Raspberry Pi might also work without external components just using internal pullups.

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VOLK v3.1.0 volk_32fc_s32f_atan2_32f() anomaly on input element 0+0j

VOLK v3.1.0 volk_32fc_s32f_atan2_32f() returns -NaN when input has a 0+0j element for the avx2 and avx2_fma kernels.

Note: j denotes an imaginary number, where j^2 = -1.

Summary

VOLK v3.1.0 volk_32fc_s32f_atan2_32f() returns -nan for the following kernels:

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#!/usr/bin/env python3
# Pyaudio output device for 32-bit floating audio input from stdin
import pyaudio
import signal
import sys
import time

argvs = sys.argv
argc = len(argvs)