AT32F413 Unlock — What You Need to Know First
The AT32F413 is an ARM Cortex-M4F microcontroller from Artery Technology (雅特力), running at up to 200 MHz with 256 KB flash and 64 KB SRAM. It is widely used in industrial control, motor drives, and consumer electronics — particularly as a cost-effective alternative to STM32F4-series parts. When the original firmware source is lost, the developer leaves a project, or a legacy product needs maintenance, AT32F413 unlock (authorized flash readout) becomes the critical recovery path.
Our engineers have handled dozens of Artery AT32 family recoveries. Below we break down the protection mechanism, realistic feasibility, costs, and the process we follow — so you can decide whether AT32F413 unlock fits your situation before committing a single dollar.
How Does the AT32F413 Protect Its Firmware?
Artery’s AT32F413 implements a Flash Access Protection (FAP) scheme closely modeled on STM32’s Read-Out Protection (RDP). It uses option bytes stored in a dedicated information block to control debug access and flash readability. There are effectively two meaningful states:
| Protection Level | Option Byte Value | Debug Access | Flash Readout | Unlock Feasibility |
|---|---|---|---|---|
| Level 0 (unprotected) | 0xA5 | Full SWD/JTAG | Allowed | No unlock needed |
| Level 1 (standard) | Any value ≠ 0xA5, ≠ 0xCC | Restricted | Blocked via SWD | High — our primary target |
| Level 2 (permanent) | 0xCC | Fully disabled | Permanently blocked | Very limited; often destructive |
Most production AT32F413 boards ship at Level 1. At this level, SWD and JTAG connections are alive but the flash read command is rejected by the bus matrix. The SRAM remains partially accessible, and the system bootloader (UART/USB DFU) may still respond — both facts our recovery techniques rely on.
Level 2 — The Hard Boundary
If the option byte is set to 0xCC, the debug port is permanently disabled at the silicon level. There is no known non-invasive path back. Invasive methods (decapping, micro-probing) are theoretically possible but cost-prohibitive for a sub-$3 MCU and carry high data-loss risk. We will always test the protection level before quoting and will tell you honestly if Level 2 makes recovery impractical.
What Makes AT32F413 Unlock Technically Feasible?
Artery’s FAP implementation on the AT32F4xx series shares architectural similarities with early STM32F1/F4 RDP, but with Artery-specific boot ROM behavior and bus timing. Our approach exploits known weaknesses in the Level 1 boundary — specifically, race conditions during the transition between boot ROM execution and user-code handoff, combined with voltage and clock manipulation that can widen the read window.
Key factors that affect success on a specific AT32F413 sample:
- Silicon revision: Earlier die revisions (pre-2022 date codes) tend to have wider timing margins. Newer revisions may have tightened the boot sequence, reducing but not eliminating the window.
- Flash size variant: The 256 KB variants (AT32F413CBT7, AT32F413RBT7) require longer extraction sessions than 128 KB parts, increasing the chance of a partial read that needs verification passes.
- Package condition: Corroded or reballed chips with marginal solder joints can lose SWD contact mid-extraction. We prefer boards over loose chips when possible.
- Boot mode pins: BOOT0/BOOT1 configuration determines whether the part enters system memory or user flash on reset — we need controlled access to these.
Realistic Success Rates and Caveats
For AT32F413 parts confirmed at Level 1 protection, our historical success on firmware extraction is in the range of 85–95% depending on silicon revision and sample condition. The remaining 5–15% of cases typically fail due to:
- Newer silicon revisions with patched boot ROM timing
- Physically damaged flash cells (ESD events, over-voltage)
- Parts that were actually set to Level 2 despite client belief otherwise
We never guarantee 100% success — any vendor who does is not being straight with you. What we do guarantee is a free feasibility assessment and no charge if extraction fails.
AT32F413 Unlock Process — Step by Step
1. Feasibility Check (Free)
Ship us the target board or bare IC. We connect via SWD, read the option bytes, confirm the FAP level, and verify flash integrity with a boundary scan. Turnaround: 1 working day after receipt.
2. Quotation
Based on the confirmed protection level, flash size, and silicon revision, we issue a fixed-price quote. You also receive an NDA and a brief authorization form confirming you own the IP or have rights to the firmware.
3. Extraction
Our lab performs the readout using proprietary tooling. For a typical 256 KB AT32F413, extraction plus two verification passes takes 2–4 working days. We compare CRC32 checksums across passes to confirm data integrity.
4. Deliverables
You receive the firmware as a binary (.bin) or Intel HEX (.hex) file, plus a brief extraction report noting the option byte state, flash size, and any anomalies. If you also need the flash reprogrammed into new blank AT32F413 parts, we can provide a programming service at additional cost.
Check feasibility for your project
Send the chip marking or board details and tell us what you need to recover. Add clear photos if available.
Request a feasibility reviewCost and Turnaround at a Glance
| Parameter | Typical Range | Notes |
|---|---|---|
| Feasibility assessment | Free | 1 working day after sample receipt |
| Level 1 unlock (128 KB) | $350–$600 | Lower end for older revisions |
| Level 1 unlock (256 KB) | $450–$800 | Two verification passes included |
| Level 2 attempt (invasive) | $1,500+ (quoted case-by-case) | Success not guaranteed; requires discussion |
| Total turnaround | 3–5 working days | From sample receipt to file delivery |
| Rush service | +40–60% | Priority queue, 1–2 day extraction |
Pricing depends on batch size, silicon revision, and whether you need additional services like BOM extraction or STM32F072 flash recovery on the same board. Multi-chip orders from the same project typically qualify for a volume discount.
AT32F413 vs. Similar MCUs — Protection Comparison
Engineers often ask how the AT32F413 compares to other Cortex-M parts they may also need recovered. Here is a quick reference:
| MCU | Vendor | Protection Scheme | Level 1 Unlock Difficulty |
|---|---|---|---|
| AT32F413 | Artery | FAP (2-level + permanent) | Moderate |
| AT32F421 | Artery | FAP (similar) | Moderate — smaller flash, faster extraction |
| MindMotion MM32F103 | MindMotion | Flash protection similar to STM32F1 | Moderate to Low |
| Nations N32G45 | Nations Tech | RDP-style, 2 levels | Moderate |
| HDSC HC32F460 | HDSC / Huada | Multi-zone protection | Moderate to High |
If your project board contains multiple protected MCUs — say an AT32F413 main controller alongside an STM8S207 co-processor — we can handle both in a single engagement, saving shipping time and coordination overhead.
Authorization and Legal Requirements
AT32F413 unlock is performed strictly as an authorized firmware recovery service. Before extraction begins, we require written confirmation that you are the IP owner, the original developer, or hold documented authorization from the rights holder. Typical legitimate scenarios include:
- Original developer lost source code due to drive failure or personnel departure
- Legacy product maintenance where the design house no longer exists
- Prototype recovery for a product you designed and own
- Court-ordered forensic analysis with proper documentation
We operate under NDA for every engagement and will decline work that lacks clear ownership proof. This protects both parties and keeps the service within legal boundaries worldwide.
Frequently Asked Questions
Can AT32F413 Level 2 protection be bypassed?
Level 2 (option byte 0xCC) permanently disables the debug interface at the hardware level. Non-invasive bypass is not possible. Invasive methods involving decapping and micro-probing exist but carry high risk of data loss and cost upward of $1,500. We assess each Level 2 case individually and will advise honestly if recovery is not practical.
Is the AT32F413 the same as an STM32F413 for unlock purposes?
No. While Artery designed the AT32F4xx series to be pin-compatible and software-compatible with STM32F4, the boot ROM, option byte layout, and flash controller implementation differ at the silicon level. Techniques that work on STM32F413 do not directly transfer to AT32F413 — and vice versa. We maintain separate toolchains for each family.
Do I need to send the whole PCB or just the chip?
Either works, but we prefer the complete board. A mounted chip gives us stable power rails, known BOOT pin states, and eliminates the risk of damage during desoldering. If you must send a bare IC, use an anti-static tube or tray and note the original BOOT0/BOOT1 configuration.
What file format will I receive after AT32F413 unlock?
Standard deliverables are a raw binary (.bin) and an Intel HEX (.hex) file covering the full flash range. We also provide a short report with CRC32 checksums, option byte dump, and any notes on flash anomalies. If you need an ELF or Motorola S-record, let us know at quote stage.
How do I confirm my AT32F413 is at Level 1 before shipping?
Connect via SWD using an AT-Link or J-Link probe. If you can halt the core and read SRAM but flash reads return all 0x00 or 0xFF, the part is almost certainly at Level 1. If the SWD port does not respond at all (no IDCODE), suspect Level 2. We verify this definitively upon receipt at no charge.
Check feasibility for your project
Send the chip marking or board details and tell us what you need to recover. Add clear photos if available.
Request a feasibility reviewWorking on a board like this?
Send the chip marking or two photos. You get feasibility, lead time and price within 24 hours, and the check costs nothing.
Get a free quote