locnnil

Notes

export CC="/usr/bin/arm-none-eabi-gcc"
export CXX="/usr/bin/arm-none-eabi-g++"
export AS="/usr/bin/arm-none-eabi-as"
export LD="/usr/bin/arm-none-eabi-ld"
export AR="/usr/bin/arm-none-eabi-ar"
export NM="/usr/bin/arm-none-eabi-nm"

locnnil

#!/bin/bash

set -e

help() {
    echo -e "${COLOR['RED']}Usage: sudo $(basename "$0") <go version> <arch> ${COLOR['END']}"
    echo -e "${COLOR['RED']}Options: ${COLOR['END']}"
    echo -e "${COLOR['RED']}  <go version>, The version of GO in format: MAJOR.MINOR.PATCH.${COLOR['END']}"
    echo -e "${COLOR['RED']}               example: sudo $(basename "$0") 1.20.6           ${COLOR['END']}"
    echo -e "${COLOR['RED']}  <arch>, The CPU arch (default amd64) ${COLOR['END']}"

locnnil

#!/bin/bash

## This is a simple script to update
## all packages of a server and 
## install docker all in one shot.
## Enjoy! :D

sudo apt-get update && sudo apt-get upgrade -y

for pkg in docker.io docker-doc docker-compose podman-docker containerd runc; do sudo apt-get remove $pkg; done

locnnil

BOOT MODE: NAND
ddr init

U-Boot 2013.04 (Oct 11 2016 - 11:22:42)

CPU:   Cortex-A9 400 MHz
AHB:   100 MHz
APB:   50 MHz

locnnil

How to compile statically linked OpenVPN client for ARMv5

You need to install ARMv5 gcc cross compiler: apt-get install gcc-arm-linux-gnueabi

You have to define a directory (via --prefix) where all of your binaries will be installed (copied). In the guide I use the following: /home/user/vpn_compile

OpenSSL

1. Download the source: wget https://www.openssl.org/source/openssl-1.0.2j.tar.gz

locnnil

cmake_minimum_required(VERSION 3.22)

SET(CMAKE_C_STANDARD 11)
SET(CMAKE_CXX_STANDARD 20)

project(template)

SET(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wall -Wno-unused-variable -Werror -Wfatal-errors ")
SET(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wall -Wno-unused-variable -Werror -Wfatal-errors")

locnnil

# CMake toolchain file for building ARM software on OI environment

# Processor
SET(CMAKE_SYSTEM_PROCESSOR arm)
# this one is important
SET(CMAKE_SYSTEM_NAME Linux)
#this one not so much
SET(CMAKE_SYSTEM_VERSION 1)

# (OPTIONAL) specify some CPU flags

locnnil

cmake-3.19.4/*
##### Windows
# Windows thumbnail cache files
Thumbs.db
Thumbs.db:encryptable
ehthumbs.db
ehthumbs_vista.db

# Dump file
*.stackdump

locnnil

Calculate the necessary CRC type

Beeing B the number of bytes of your message the necessary numbers necessary in your CRC gonna be:

N >= ln(8*B+1)/ln(2) -1

This formula cames from the manipulation of the formula B = (2**(N+1) -1)/8

OBS: rembering that only exists CRC8, CRC16 and CRC32 (until now)

locnnil

The size of a Array in C

• Using sizeof:

int a[17];
size_t n = sizeof(a) / sizeof(a[0]);

• Using a Macro function

#define NELEMS(x) (sizeof(x) / sizeof((x)[0]))