destogod/re/disx.py
type-two 07977624ae DestoGod: replacement for the TP5 bus destination sign software
TP5 is a 2012 Windows application supplied with the Guangzhou-Tongda LED
destination signs fitted to Yutong buses. It has no preview, so building a
destination list is guess-and-check, and it only runs on Windows.

The bus never talks to TP5 — the sign controller reads a .td5 file off an SD
card, and that is the whole interface. So this replaces the software without
touching any hardware or protocol: it just has to write byte-correct .td5.

Formats reverse-engineered from the sample files and TP5(En).exe, then verified
byte-for-byte:

  .td5   the file the bus reads. Fixed-layout binary; each destination block
         carries a CRC-16/ARC over block[3..len] and a rand() block id, which
         together looked like one 4-byte field because RAND_MAX is 0x7fff.
  .tp5   the editable project. Line-based text, UTF-16BE hex strings.
  .font  the sign's own bitmap fonts, each glyph row XORed with its char code.

The app is one self-contained HTML file: live LED preview at the real sign size
with real scrolling, spreadsheet/CSV import, multi-page destinations, undoable
delete, and export to both .td5 and .tp5.

Verified:
  - rebuilds a real 46,080-byte TP5 export byte-for-byte with a recomputed CRC
  - all 36 stored CRCs verify against the implementation
  - driven through its own UI, re-exporting the real file differs in 7 bytes,
    all of them the export timestamp
  - running on a real bus: signs and driver's controller both correct

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
2026-08-21 13:06:25 +10:00

32 lines
943 B
Python

import sys, struct
from capstone import *
import pefile
EXE = sys.argv[3] if len(sys.argv)>3 else '/Users/jing/Documents/yutong/yutongapp/TP5(En).exe'
d = open(EXE,'rb').read()
BASE = 0x400000
pe = pefile.PE(EXE)
# import name map
imp = {}
for e in pe.DIRECTORY_ENTRY_IMPORT:
for i in e.imports:
imp[i.address] = (e.dll.decode(), i.name.decode() if i.name else 'ord%d'%i.ordinal)
md = Cs(CS_ARCH_X86, CS_MODE_32)
md.detail = True
start = int(sys.argv[1],16)
n = int(sys.argv[2],16) if len(sys.argv)>2 else 0x200
off = start - BASE
for ins in md.disasm(d[off:off+n], start):
s = "%08x %-24s %s %s" % (ins.address, ins.bytes.hex(), ins.mnemonic, ins.op_str)
# annotate indirect calls
if ins.mnemonic in ('call','jmp') and 'dword ptr [0x' in ins.op_str:
try:
a = int(ins.op_str.split('[')[1].split(']')[0],16)
if a in imp: s += ' ; %s!%s' % imp[a]
except: pass
print(s)