> For the complete documentation index, see [llms.txt](https://wiki.inels.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://wiki.inels.com/inels-bus/inels-design-manager-idm3/connecting-and-uploading-to-the-central-unit.md). # Connecting and uploading *Part 3 — Reference.* *** ## 23.1 The two directions | Direction | Menu item | Effect | | --------- | -------------------------- | ---------------------------------------------------- | | PC → CU | **Save to central unit** | Uploads your project. **This changes the building.** | | CU → PC | **Load from central unit** | Downloads whatever the CU is running | Both are on `[☰]` and on the **Project** ribbon tab. > **Save writes a file. Save to central unit changes the installation.** Nothing you do in iDM3 affects the building until you upload. *** ## 23.2 Setting up the connection `[☰]` → **Settings** → **Connection settings**: | Field | Meaning | | --------------------- | --------------------------------- | | **IP address : port** | The CU's address | | **Timeout (ms)** | How long to wait before giving up | | **Ping test** | Checks the CU answers | **Always run Ping test first.** It separates a network problem from a project problem in one click, and saves a lot of time chasing the wrong thing. There is also **IP address from project** in the main menu, which uses the address stored in the project rather than the one in Settings. *** ## 23.3 Connection states Shown at the bottom right of the main window: | State | Meaning | What to do | | ---------------- | ------------------- | ----------------------------------------------------------------------------------------------------------------------- | | `Disconnected` | Not connected | Check the IP address and network | | `Connecting` | In progress | Wait | | `Connected` | Connected | You can upload and monitor | | `Disconnecting` | Closing | Wait | | `BadPassword` | Wrong CU password | You will see *"Please try it again."* | | `UpdateRequired` | CU firmware too old | *"Please update CU firmware."* — see [Chapter 25](/inels-bus/inels-design-manager-idm3/idm3-firmware-update-manager.md) | | `Error` | Failed | Read the information console | | `NotSpecifed` | No state | — | *** ## 23.4 Uploading 1. `[☰]` → **Save to central unit**. 2. Confirm. 3. Watch the progress dialog and the information console. iDM3 **compiles** the project first. If compilation fails the **Compile error** button on the **Project** ribbon tab lights up — click it to see what is wrong. Nothing is uploaded. > **Save your project before uploading.** If the upload reveals a problem, you want the file on disk to match what you sent. *** ## 23.5 Downloading `[☰]` → **Load from central unit**. iDM3 asks *"Load project from CU?"* before replacing what you have open. This is how you pick up an installation you have never seen — the CU holds the whole configuration, including the original names. *** ## 23.6 Are they the same? iDM3 compares your project against the CU using hashes, and reports: | Message | Meaning | | ----------------------------------------------- | -------------------------------------------- | | *"Projects are the same."* | The CU is running exactly what you have open | | *"Projects are NOT the same!"* | They differ | | *"Projects tree is \[x], system tree is \[y]."* | Which parts differ | The Monitor shows related indicators — **Set actions simulated by CU**, **Structure simulated on CU** and **System structure simulated on CU**. **Check this before making changes on an unfamiliar site.** If the CU is running something other than the file you were given, uploading your file silently discards whatever was there. *** ## 23.7 Passwords and user levels The project holds two users, **Admin** and **User**, each with an optional password. `BadPassword` means the CU has a password your project does not match. *** ## 23.8 Auto restore `[☰]` → **Settings** → **Auto restore project at the CU**. *** ## 23.9 Super-user mode The Start menu includes **iDM3 SuperUser**, which runs `IDM3.SuperUser.cmd` and unlocks settings hidden from ordinary users. **Do not use it for normal work.** Those settings are hidden because getting them wrong can break a working installation. Use it only when ELKO EP support asks you to. *** ## 23.10 When an upload does not work | Symptom | Check | | ------------------------------------------- | ----------------------------------------------------------------------------------------------------------- | | `Disconnected` | IP address, cabling, that the CU is powered | | Ping test fails | It is a network problem — fix that first | | `BadPassword` | The CU password | | `UpdateRequired` | Update the CU firmware ([Chapter 25](/inels-bus/inels-design-manager-idm3/idm3-firmware-update-manager.md)) | | **Compile error** lights up | Click it and read the error | | Upload succeeds, nothing changes | Yellow dots on the Design tab; wrong addresses in Device manager | | *"Projects are NOT the same!"* after upload | The upload did not complete — check the console | More in [Chapter 30](/inels-bus/inels-design-manager-idm3/troubleshooting-idm3.md). *** **Next:** [Chapter 24 — External systems](/inels-bus/inels-design-manager-idm3/idm3-external-systems-mqtt-modbus-cloud.md).