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@demech
demech / imx7d-512mb-ram.md
Last active May 7, 2024 09:50
Configure iMX7D to support 512MB DRAM

The iMX7D reference design has two 512MB of RAM for a total of 1GB (math). With RAM costs on the cheap it is likely that your custom embedded platforms with the iMX7D will also have 1GB of RAM. But what happens when you are trying to cut costs, or just not over engineer and go with a single 512MB.

There are some tutorials online, but I couldn't find one that included all the changes that need to be made. So here I am.

There are some things to know before going further. I was using Das U-boot for my bootloader, and working with a linux kernel new enough to have DTS files (I think that happened in 3.7 for ARM architecture).

U-boot

We'll start in u-boot and go up from there. The iMX7D DCD (Device Configuration Data) file is located in the board directory as imximage.cfg There are 5 values that need to be changed and they are, the Master Register and Address Map Registers 0/1/5/6. Search the iMX7D Reference Manuel for more information on each of the registers.

-DATA 4 0x307a0000 0x01040001

@liquidx
liquidx / imx7-README.md
Last active May 7, 2024 09:49
Reflashing a TechNexion PICO-PI-IMX7

By: Alastair Tse @liquidx

Updated: 2021-12-05

This is a guide for installing Linux on a Technexion NXP IMX7 board. This is a board that was part of the Android Things Starter Kit (now discontinued).

There are some dead ends in this guide where I got to a point where I failed. I'm documenting this so that it can help anyone else who is trying the same thing.

Before starting, there are a few useful sources of information:

@roylee0704
roylee0704 / dockergrep.sh
Created December 9, 2016 08:24
how to grep docker log
docker logs nginx 2>&1 | grep "127."
# ref: http://stackoverflow.com/questions/34724980/finding-a-string-in-docker-logs-of-container
@borispoehland
borispoehland / effects.ts
Last active May 7, 2024 09:48
3 fetch effects for effect-ts. One uses cache: no-store, one cache: force-cache and one uses the default cache / revalidate
import * as S from '@effect/schema/Schema'
import { Context, Effect } from 'effect'
export interface IFetcher {
fetch: typeof fetch
}
export const TFetcher = Context.Tag<IFetcher>('IFetcher')
class FreshFetcher implements IFetcher {
@hhc0null
hhc0null / your_first_format_string_attacks.md
Last active May 7, 2024 09:47
fsbの資料

Your First Format String Attacks.

1. What's the `Format String Bugs'?

　Format String Bugs(以降, FSBとする)とは, sprintf()やfprintf()などのprintf関数群やsyslog()などのFormat Strings(以降, 書式指定子とする)を扱える関数において, ユーザが自由に書式指定子を配置できるバグである. これを利用した攻撃手法をFormat String Attacksと呼び, この攻撃によりターゲットとなるプロセスがアクセス可能な任意のメモリの読み書きが行えるようになる. また, それを利用しプログラムの制御を乗っ取ることも可能である.
　実際のプログラムに多く存在するとは到底言えないような脆弱性ではあるが稀に見つかることはある. CVE-2012-0809[1]ではsudoのデバッグ機能にFSBが見つかり, 実際にlocal exploitが公開されたりもした. 前述の通り珍しいものではあるが, 任意のメモリの書き換えができるなど非常に強力なものであることからCTFではよく題材にされる.
　この記事ではFSBの検証に以下の環境を使用した.

sh-4.3$ uname -a
Linux Arch_Laptop 4.0.4-1-ARCH #1 SMP PREEMPT Mon May 18 06:43:19 CEST 2015 x86_64 GNU/Linux
@dwilliamson
dwilliamson / MarchingCubes.js
Last active May 7, 2024 09:46
Marching Cubes Lookup Tables
//
// Lookup Tables for Marching Cubes
//
// These tables differ from the original paper (Marching Cubes: A High Resolution 3D Surface Construction Algorithm)
//
// The co-ordinate system has the more convenient properties:
//
// i = cube index [0, 7]
// x = (i & 1) >> 0
// y = (i & 2) >> 1
@bugcy013
bugcy013 / NSE_Reports_link.txt
Last active May 7, 2024 09:46
NSE Reports link
@tanaikech
tanaikech / submit.md
Last active May 7, 2024 09:45
Gemini API with JSON schema

Gemini API with JSON schema

Overview

These are sample scripts in Python and Node.js for controlling the output format of the Gemini API using JSON schemas.

Description

In a previous report, "Taming the Wild Output: Effective Control of Gemini API Response Formats with response_mime_type," I presented sample scripts created with Google Apps Script. Ref Following its publication, I received requests for sample scripts using Python and Node.js. This report addresses those requests by providing sample scripts in both languages.

@sid24rane
sid24rane / StackBalancedParenthesis.c
Created September 28, 2016 17:55
Balanced Parenthesis in C using stack
#include <stdio.h>
#include <stdbool.h>
#include <string.h>
#define MAX_SIZE 100
struct Stack{
int top;
char arr[MAX_SIZE];
} st;
@luismts
luismts / GitCommitBestPractices.md
Last active May 7, 2024 09:43
Git Tips and Git Commit Best Practices

Git Commit Best Practices

Basic Rules

Commit Related Changes

A commit should be a wrapper for related changes. For example, fixing two different bugs should produce two separate commits. Small commits make it easier for other developers to understand the changes and roll them back if something went wrong. With tools like the staging area and the ability to stage only parts of a file, Git makes it easy to create very granular commits.

Commit Often

Committing often keeps your commits small and, again, helps you commit only related changes. Moreover, it allows you to share your code more frequently with others. That way it‘s easier for everyone to integrate changes regularly and avoid having merge conflicts. Having large commits and sharing them infrequently, in contrast, makes it hard to solve conflicts.