---
title: M.2 modules
slug: one/testing/m2-modules
docTags: 
createdAt: 2026-06-10T18:09:43.959Z
---

This section covers M.2 expansion modules testsing. Flipper One has M.2 Key-B (S3), has USB and PCIe interfaces in M.2 port.

### M.2 Port tech specification

![](https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/vXsDRyBoang0cQGn1wfUZ_photo-2026-01-26-113802.jpeg)

## Auto config detection

In the M.2 spec, **CONFIG pins** are **strap / detection pins** used by the **host** (and sometimes the module) to determine:

- What **interface** the module expects (USB vs PCIe) 
- What **role or mode** should it boot in
- sometimes the **module class** (WWAN, SSD, etc.) 

They are **sampled at power-up or reset**.

Depending on the **M.2 key**, different pins are used:

- **Key B / B+M (WWAN modems).** Common CONFIG-related pins: 
  - `CONFIG_1`
  - `CONFIG_2` 
  - sometimes reused **GPIO / LED / UART pins** 
- **Key M (SSDs).** Mostly PCIe / SATA focused, CONFIG pins usually select: 
  - PCIe vs SATA 
  - lane width (x2 / x4) 

 For **modems**, this is much more vendor-specific than for SSDs.

### ❓❓ How to test detect pins?❓❓

## M.2 modems 

![](https://api.archbee.com/api/optimize/3StCFqarJkJQZV-7N79yY/fQ5U0c1Dg1ydEB4AbfKoP_image.png)

M.2 modems can vary significantly:

- Different form factors. Flipper One supports only 30×52 and 30×42. 
- Different connection interfaces: USB and PCIe. 
- Different auxiliary pins: UART, LED, and other signals may be routed to unused pins of the M.2 connector.

### SIM-card test

1. Install SIM-card in Flipper One port 
2. Verify that it visible on modem

### USB-only modem 

1. Verify that modem only has USB interface 
2. Connect that it works properly

### PCIe-only modem 

1. Verify that modem only has PCIe interface (its exist?)
2. Connect that it works properly

### PCIe+USB modem

1. Verify that modem only has both PCIe+USB interfaces
2. Connect that it works properly

### Modem activity LED pins 

Most M.2 modems have activity LED on some pins. 

## SSD Disk

TODO