Dr. Christian Giessen 6849a701d4 Fix Type 1 AMF bitfield and add real FIR/IIR test ROMs
- Fix Type 1 multifunction: AMF=bits17-13, DD=bits19-18, PD=bits21-20
  (was off by one bit, causing wrong MAC decode on real firmware)
- Add FIR filter ROM (fir.bin): 52 instructions, assembled from AD example
- Add IIR biquad ROM (iir.bin): 28 instructions, assembled from AD example
- Add open21xx-compatible source files (build/fir.dsp, build/iir.dsp)
- Both ROMs disassemble correctly showing expected DSP patterns:
  MAC+dual-read kernels, DO UNTIL loops, ASHIFT scaling, RTS(DB)
- Full regression: isa_test.bin unchanged
2026-04-22 19:47:12 +00:00

ADSP-219x Reverse Engineering Toolkit

Radare2 architecture plugin and reference materials for reverse engineering ADSP-2191 firmware.

Contents

r2plugin/       Native radare2 arch plugin (C, GNU style)
examples/       ADSP-2191 assembly examples (FIR, IIR, FFT, Viterbi)
                + assembler-verified ISA test ROM
testrom/        Test ROM generator for plugin validation
docs/           Architecture reference, opcode tables, walkthrough guides

Quick Start

cd r2plugin && make && make install
r2 -a adsp219x -b 24 examples/isa_test.bin
[0x00000000]> pd 48

Requirements

  • Radare2 >= 5.8.0 (RArchPlugin API)
  • GCC

Plugin Status

Currently decodes: NOP, IDLE, Type 1 (multifunction), Type 3 (direct memory), Type 4 (compute + memory), Type 6/7 (immediate loads), Type 10/10a (jump/call), Type 17 (reg move), Type 20 (RTS/RTI).

Work in progress: Type 9/9a (standalone compute), Type 11 (DO UNTIL), Type 15 (shift), Type 18 (mode control), Type 25 (saturate).

Assembler

The examples were assembled with open21xx, an open-source assembler/linker for ADSP-218x/219x. Build instructions are in the open21xx README. The resulting ELF is converted to raw binary with dd (extract the int_pm section).

License

Plugin code: LGPL-3.0-only. Example code from Analog Devices application notes. Documentation extracts from the ADSP-219x DSP Instruction Set Reference.

Description
ADSP-2191 Reverse Engineering - Disassembler, radare2 plugin, and analysis tools
Readme 2.1 MiB
Languages
C 50.4%
Python 48.6%
Makefile 1%