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John-K / Header.html
Created January 30, 2025 18:14
GP_SPIFI SPI Flash dump documentation for Tiny TV Classic
<pre style="display: grid; grid-template: 'container';"><code class="language-annotated-hexdump" style="grid-area: container; line-height: 1.2;">00000000 47 50 5F 53 50 49 46 49 01 01 00 00 00 00 00 00 GP_SPIFI........
00000010 00 00 00 00 00 00 00 02 00 3E 21 07 00 00 00 00 .........&gt;!.....
00000020 78 00 2F 00 43 4C 41 53 53 49 43 00 00 00 00 00 x./.CLASSIC.....
00000030 4A 55 52 41 53 53 49 43 20 50 41 52 4B 20 56 34 JURASSIC PARK V4
00000040 04 00 00 00 01 00 00 00 02 00 00 00 03 00 00 00 ................
00000050 04 00 00 00 FF FF FF FF FF FF FF FF FF FF FF FF ....ÿÿÿÿÿÿÿÿÿÿÿÿ
General Plus SPI Flash Interface magic number
version?
data size
@John-K
John-K / PSP HW Regs.md
Last active January 17, 2023 02:31
PSP 0xBCxxxxxx Register Descriptions

0xbc10003c

  • 0x1 - sceSysreg_driver_0x4841B2D2(int) (set), sceSysreg_driver_0x4E5C86AA (read, clear, restore)
    • also if (int == 0) reg &= 0xe0000000
  • 0x1 - sceSysregDoTimerEvent(0, 1 or 3) (set), sceSysregDoTimerEvent(0, 0 or 2) (clear)
  • 0x2 - sceSysregDoTimerEvent(1, 1 or 3) (set), sceSysregDoTimerEvent(1, 0 or 2) (clear)

0xbc100040

  • (>> 8) - sceSysregGetTachyonVersion
  • 0x100 - sceSysregSetAwEdramSize(arg1)
  • if (tachyonVersion &gt;= 0x500000)
@John-K
John-K / me_wrapper.c
Last active October 6, 2020 04:07
me_wrapper.prx
// func_00002070
// sceMeWrapper_driver_0x24317CD0
int module_start(void) {
int tachyonVersion;
float pllFreq;
undefined4 local_20;
int local_1c;
initMEAtomicsAndInterruptHandler();
sceLfatfsWaitReady();
@John-K
John-K / covid.py
Created March 29, 2020 19:52
parse NYT covid data into python dictionaries
#!/usr/bin/env python
# run from the NYT data directory:
# python covid.py
import csv
import pprint
# data structures
@John-K
John-K / minignore.go
Created August 12, 2019 17:08
go script to minimize gitignore rules for those super hairy repos
// minignore.go
// John Kelley <[email protected]>
// January 2019
// Covered by BSD license
//
// minignore parses all of the rules in your gitignore files and omits those rules which are covered by others
// (including duplicate lines). The output is written to the given path with '.new' appended to the filename
//
// Usage: go run minignore.go .gitignore
@John-K
John-K / gist:b2dae21562a70fb51ed8151ffc876951
Last active May 15, 2018 18:45
CH554 Quickstart Guide
See examples, headers, english datasheet from https://github.com/Blinkinlabs/ch554_sdcc
Open source wchisp https://github.com/rgwan/librech551
To program, short 2-pins of ISP header as you plug board into USB
@John-K
John-K / crc32_brute.c
Last active June 5, 2018 05:38
Reverse Engineering a Book Cover: bruteforcing crc32 values
//gcc -msse4.2 brute.c
#include <stdio.h>
int crc32(int crc, char c) {
return __builtin_ia32_crc32qi(crc, c);
}
int main() {
int value = 0;
int tableIndex = 22;
int table[] = {0x564d94ce,0x56487985,0xcd6966e6,0x791b5538,0xbdc0bfb7,0x8ecbf593,0xc652c4a2,0x94a3ebf7,0x2673b49e,0x89f7731e,0x32c1eb44,0x7886f083,0x52e2bb44,0xc7fdffaa,0x69f9005a,0xe04743ac,0x44229524,0xe8032961,0x8cc30f1e,0x084cdea3,0xeb48d1ad,0x90809740,0xe4292d5a };
@John-K
John-K / cover_re.py
Last active June 5, 2018 05:29
Reverse Engineering a Book Cover
#!/bin/env python2
# -*- coding: utf-8 -*-
# Solution to Book Cover Crackme from "Praktyczna inżynieria wstecznia
# Edited by Gynvael Coldwind and Mateusz Jurczyk. (Applied Reverse Engineering)
# PWN Bookstore: https://ksiegarnia.pwn.pl/Praktyczna-inzynieria-wsteczna,622427233,p.html
#
# Props to @radekk for his excellent writeup and for capturing the flag. Read his
# writeup at https://vulnsec.com/2017/reverse-engineering-a-book-cover/
#
# This was a fun opportunity to learn how to use Unicorn Engine, Capstone Engine,
@John-K
John-K / cmv_snap3.c
Last active May 21, 2016 09:18
Apertus cmv_snap3 flipped ordered pixel output
664 union dpixel {
665 uint32_t p;
666 uint8_t b[4];
667 } pix_out;
668 for (int frame = 0; frame < num_frames; frame++) {
669 for (int row = 0; row < 3072; row+=2) {
670 //
671 // pixel order is (1,0) (1,1) (0,0) (0,1) <16-bit overlay> when in flipped mode
672 // 52^ 40^ 28^ 16^
673 for (int i = 0; i < 32*128*2/4; ++i) {
@John-K
John-K / vpn nat
Created April 1, 2016 03:15
#!/bin/sh
natd -interface tun0
ipfw -f flush
ipfw add divert natd ip from any to any via tun0
ipfw add pass all from any to any
sysctl -w net.inet.ip.forwarding=1