> For the complete documentation index, see [llms.txt](https://docs.smart-stuff.nl/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.smart-stuff.nl/p1-modbus-dongle/firmware-v2-current/firmware-v2.md).

# Firmware v2 overview

Firmware v2 is the shared current software layer for supported Smart Meter Modbus Adapters. Instead of installing a separately compiled firmware variant for each application, v2 contains all supported Modbus mappings in one firmware image. Mapping, communication settings, monitoring and device control are handled at runtime through the Device Manager.

{% hint style="info" %}
P1 Modbus Pro units shipped from 15 June 2026 use firmware v2. D1MC supports firmware v2 as its only Modbus firmware generation.
{% endhint %}

Older P1 Modbus adapters currently running firmware v1 can be upgraded. Follow [Migrate from v1 to v2](/p1-modbus-dongle/firmware-v1-legacy/migrate-to-v2.md) because the current mapping and communication settings must be recorded and restored after installation. Firmware v1 does not apply to D1MC.

## Fundamental difference

| Firmware v1                                                         | Firmware v2                                                 |
| ------------------------------------------------------------------- | ----------------------------------------------------------- |
| Separate firmware variant for each mapping or use case              | One firmware image containing all mappings                  |
| Reflash to change to another mapping variant                        | Select another mapping in the Device Manager                |
| Configuration mainly through Modbus registers and compiled defaults | Configuration and device control through the Device Manager |
| Basic status and update workflow                                    | Live status, Modbus monitor and integrated updates          |

## Main changes from v1

* Selectable Modbus mappings in one firmware image
* Configuration through the USB Device Manager
* Live device, P1 and Modbus status
* Persistent configuration stored on the adapter
* Integrated stable firmware check and update flow
* Modbus request monitor for diagnostics
* Improved RGB status indications and hardware diagnostics
* Support for DSMR/P1 and, on compatible hardware, HAN-NVE as the smart-meter source

## Mappings included in firmware v2

The following mappings can be selected in the Device Manager without installing different firmware:

* Default - TeltoCharge
* Default - floats
* SDM630
* DTSU666
* Alfen
* EM330
* EM111
* ABB B21
* EMPRO / MX3xx
* KLEFR / Inepro
* Phoenix Contact EEM / XM3xx
* Charge Pro
* DRIS
* Wallbox - P1MB
* SolarEdge
* SunSpec 203

## Default configuration

* Mapping: Default - TeltoCharge
* Modbus device ID: `43`
* RS485: `38400 8E1`
* Smart-meter source: DSMR/P1 (`SMR (P1)` in the current Device Manager)

These values can be changed in the [Device Manager](/p1-modbus-dongle/firmware-v2-current/device-manager.md). Changing a mapping does not require a firmware update. See [Configuration](/p1-modbus-dongle/firmware-v2-current/configuration.md) for hardware applicability and setting details.

## Available mappings

Firmware v2 contains native mappings and emulations for integrations that expect a particular meter layout. See [Firmware v2 register mappings](/p1-modbus-dongle/firmware-v2-current/register-mapping.md) for the complete list and register tables generated from the v2 recipes.

## Confirmed device configurations

See [Confirmed device configurations](/p1-modbus-dongle/firmware-v2-current/confirmed-configurations.md) for settings that users have successfully applied with specific chargers, inverters and other Modbus devices.

## Updating

The preferred update method is the integrated updater in the Device Manager. See [Updating firmware](/p1-modbus-dongle/firmware-v2-current/update.md).