+# Project History

+

+## Origin

+

+This project started as a proof of concept for reverse engineering three Bluetooth-enabled USB meters sold under the Ruideng name:

+

+- `UM25(C) V2.0`

+- `UM34(C) V2.3`

+- `TC-66C`

+

+## Initial Goal

+

+The original goal was to discover how these devices expose their data over Bluetooth and to build a working software prototype capable of reading and displaying that data.

+

+## Progress Reached

+

+The project progressed to the point where data could be obtained from the devices.

+

+At that stage, active work stopped.

+

+## Current Knowledge Gaps

+

+At this point, the exact status of the reverse engineering effort is not fully known:

+

+- it is not clear which payload fields were fully decoded

+- it is not clear which payload fields remain unknown

+- it is not clear how complete the protocol understanding is for each model

+

+The project code itself is now the main surviving reference for what was achieved.

+

+## Available Resources

+

+The original external research resources are no longer available, except for what is already included in this repository.

+

+Because of that, the project should treat the existing source code and notes as the baseline for rebuilding protocol knowledge.

+

+## Current Direction

+

+The next stage is not to restart reverse engineering from scratch, but to document what is already present in the codebase and collect newly discovered materials in a structured way.

+

+That includes:

+

+- manuals

+- specifications

+- payload observations

+- protocol notes

+- reverse engineering findings for each supported meter model

+# Documentation

+

+This folder contains project notes, platform decisions, and collected reverse engineering material.

+

+It is intended to keep the repository root focused on the app itself while preserving project context in one dedicated place.

+# Manuals

+

+Place product manuals, user guides, or archived copies of vendor documentation here.

+

+Recommended naming:

+

+- include model name

+- include version or revision when known

+- include source and date when possible

+# Payload Notes

+

+Use this folder for protocol-level findings.

+

+Examples:

+

+- packet captures

+- field maps

+- command and response notes

+- unknown byte ranges

+- per-model payload differences

+

+For each note, prefer recording:

+

+- model

+- firmware or hardware revision if known

+- sample payload

+- decoded meaning

+- confidence level

+# Research Resources

+

+This folder is reserved for external and internal technical material gathered after the original proof-of-concept phase.

+

+Use it to collect:

+

+- manuals

+- vendor specifications

+- screenshots or extracts of device information

+- protocol notes

+- payload descriptions

+- decoded and undecoded field mappings

+- references to related external projects

+

+Suggested rule:

+

+- keep raw source material close to its origin

+- keep interpretation notes in Markdown

+- prefer small focused notes over large mixed documents

+# Related Projects

+

+This folder tracks external projects that may help reconstruct protocol knowledge or validate naming and decoding choices.

+# floriandotorg/um24c

+

+Repository:

+

+- https://github.com/floriandotorg/um24c

+

+## Why it matters

+

+This appears to be a contemporary external project focused on the same family of Bluetooth USB power meters.

+

+It is relevant because it covers:

+

+- `UM24C`

+- `UM25C`

+- `UM34C`

+

+These overlap substantially with the devices targeted by this project.

+

+## Quick Notes

+

+From a quick inspection, the project appears to be a web UI built around Web Bluetooth and live plotting.

+

+Potentially useful areas:

+

+- model naming conventions

+- field naming choices

+- unit scaling assumptions

+- decoded status values

+- command / payload interpretation hints

+- UI ideas for live data presentation

+

+## Observations From Initial Review

+

+- The repository describes itself as a web UI for `UM24C/UM25C/UM34C` power meters.

+- It uses a JavaScript frontend rather than native iOS code.

+- It includes explicit model mappings such as:

+  - `0x0963 -> UM24C`

+  - `0x09c9 -> UM25C`

+  - `0x0d4c -> UM34C`

+- It also includes a charging mode map with values such as `QC2`, `QC3`, `DCP1.5A`, and `SAMSUNG`.

+

+## Limits

+

+- It does not appear to target `TC-66C`.

+- It should be treated as a secondary reference, not as ground truth.

+- Any payload interpretation borrowed from it should be validated against our own code and captures.

+

+## Suggested Use

+

+Use this project mainly for:

+

+- terminology alignment

+- comparison of decoded fields

+- cross-checking known model identifiers

+- identifying gaps in our current understanding

+

+Avoid assuming protocol equivalence without validation.

+# Specifications

+

+Place technical specifications, hardware notes, BLE service descriptions, and device capability summaries here.

+

+Useful content for this folder:

+

+- radio module details

+- service and characteristic UUID notes

+- device version comparisons

+- hardware revisions

+		1C6B6B942A2D4F5100A0B001 /* Documentation README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };

+		1C6B6B8B2A2D4F5100A0B001 /* Project History.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = "Project History.md"; sourceTree = "<group>"; };

+		1C6B6B8D2A2D4F5100A0B001 /* Research Resources README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };

+		1C6B6B8F2A2D4F5100A0B001 /* Manuals README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };

+		1C6B6B912A2D4F5100A0B001 /* Specifications README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };

+		1C6B6B932A2D4F5100A0B001 /* Payload Notes README.md */ = {isa = PBXFileReference; lastKnownFileType = net.daringfireball.markdown; path = README.md; sourceTree = "<group>"; };

+		1C6B6B952A2D4F5100A0B001 /* Documentation */ = {

+			isa = PBXGroup;

+			children = (

+				1C6B6B942A2D4F5100A0B001 /* Documentation README.md */,

+				1C6B6B8A2A2D4F5100A0B001 /* Platform Decision - iOS 15.md */,

+				1C6B6B8B2A2D4F5100A0B001 /* Project History.md */,

+				1C6B6B8C2A2D4F5100A0B001 /* Research Resources */,

+			);

+			path = Documentation;

+			sourceTree = "<group>";

+		};

+		1C6B6B8C2A2D4F5100A0B001 /* Research Resources */ = {

+			isa = PBXGroup;

+			children = (

+				1C6B6B8D2A2D4F5100A0B001 /* Research Resources README.md */,

+				1C6B6B8E2A2D4F5100A0B001 /* Manuals */,

+				1C6B6B902A2D4F5100A0B001 /* Specifications */,

+				1C6B6B922A2D4F5100A0B001 /* Payload Notes */,

+			);

+			path = "Research Resources";

+			sourceTree = "<group>";

+		};

+		1C6B6B8E2A2D4F5100A0B001 /* Manuals */ = {

+			isa = PBXGroup;

+			children = (

+				1C6B6B8F2A2D4F5100A0B001 /* Manuals README.md */,

+			);

+			path = Manuals;

+			sourceTree = "<group>";

+		};

+		1C6B6B902A2D4F5100A0B001 /* Specifications */ = {

+			isa = PBXGroup;

+			children = (

+				1C6B6B912A2D4F5100A0B001 /* Specifications README.md */,

+			);

+			path = Specifications;

+			sourceTree = "<group>";

+		};

+		1C6B6B922A2D4F5100A0B001 /* Payload Notes */ = {

+			isa = PBXGroup;

+			children = (

+				1C6B6B932A2D4F5100A0B001 /* Payload Notes README.md */,

+			);

+			path = "Payload Notes";

+			sourceTree = "<group>";

+		};

+				1C6B6B952A2D4F5100A0B001 /* Documentation */,