edit node ids and no duplicate checking:

Web/candoDocument.js

@@ -848,6 +848,21 @@
 		});
 	}
 
+	function updateGrId(name, newGrId) {
+		return _withEditor(() => {
+			if (!name || !name.trim())
+				return { ok: false, error: "Node name is required" };
+			const n = name.trim();
+			if (!newGrId || !/^0x[0-9a-fA-F]+$/i.test(newGrId.trim()))
+				return {
+					ok: false,
+					error: "GR ID must be a hex value (e.g. 0x2B)",
+				};
+			_grIds.set(n, newGrId.trim());
+			return { ok: true, warnings: [] };
+		});
+	}
+
 	function addBus(deviceName, busPort) {
 		return _withEditor(() => {
 			deviceName = (deviceName || "").trim();
@@ -1424,6 +1439,7 @@
 		addDevice,
 		deleteDevice,
 		renameDevice,
+		updateGrId,
 		addBus,
 		addRoute,
 		deleteRouteEntry,

Web/formNodeEdit.js

@@ -1,8 +1,10 @@
 // Purpose: "Edit Node" modal form.
-// Allows renaming a routing device/node entry in-place. Validates that the new
-// name is non-empty and does not collide with an existing node. A no-op save
-// (same name) closes without marking any change.
-// Depends on: formUtils.js (FormUtils), editor.js (GrcanEditor).
+// Allows editing a routing device/node entry in-place: its name and its GR ID
+// (hex node ID). Validates that the new name is non-empty and does not collide
+// with an existing node, and that the GR ID is hex and not already used by
+// another node. A no-op save (name and ID unchanged) closes without marking any
+// change.
+// Depends on: formUtils.js (FormUtils), editor.js (GrcanEditor), candoDocument.js.
 // Registers: window.GrcanEditor.showRoutingNodeEditForm
 
 (function () {
@@ -13,12 +15,22 @@
 		const fu = window.FormUtils;
 		const { overlay, body, footer } = fu.createModal("Edit Node");
 
+		const oldGrId =
+			(window.GrcanDocument && window.GrcanDocument.getGrId(oldDeviceName)) ||
+			"";
+
 		const nameF = fu.makeFormRow(
 			"Node Name",
 			fu.makeInput("text", oldDeviceName || "", "Node Name"),
 			true,
 		);
+		const idF = fu.makeFormRow(
+			"Node ID (GR ID)",
+			fu.makeInput("text", oldGrId, "0x2B"),
+			true,
+		);
 		body.appendChild(nameF.row);
+		body.appendChild(idF.row);
 
 		const cancelBtn = fu.makeBtn("Cancel");
 		cancelBtn.addEventListener("click", () => fu.closeOverlay(overlay));
@@ -28,6 +40,7 @@
 
 		saveBtn.addEventListener("click", () => {
 			const newName = nameF.input.value.trim();
+			const newId = idF.input.value.trim();
 			let ok = true;
 
 			if (!newName) {
@@ -42,18 +55,45 @@
 			} else {
 				nameF.error.textContent = "";
 			}
+
+			if (!newId) {
+				idF.error.textContent = "Required";
+				ok = false;
+			} else if (!/^0x[0-9a-fA-F]+$/.test(newId)) {
+				idF.error.textContent = "Hex format (e.g. 0x2B)";
+				ok = false;
+			} else {
+				idF.error.textContent = "";
+			}
 			if (!ok) return;
 
-			if (newName === oldDeviceName) {
+			const nameChanged = newName !== oldDeviceName;
+			const idChanged = newId.toLowerCase() !== String(oldGrId).toLowerCase();
+
+			if (!nameChanged && !idChanged) {
 				fu.closeOverlay(overlay, { force: true });
 				return;
 			}
 
-			const result = window.GrcanDocument.renameDevice(oldDeviceName, newName);
-			if (!result.ok) {
-				nameF.error.textContent = result.error;
-				return;
+			if (nameChanged) {
+				const result = window.GrcanDocument.renameDevice(
+					oldDeviceName,
+					newName,
+				);
+				if (!result.ok) {
+					nameF.error.textContent = result.error;
+					return;
+				}
 			}
+
+			if (idChanged) {
+				const result = window.GrcanDocument.updateGrId(newName, newId);
+				if (!result.ok) {
+					idF.error.textContent = result.error;
+					return;
+				}
+			}
+
 			editor.markEdited("routeNode:" + newName);
 			fu.closeOverlay(overlay, { force: true });
 			editor.triggerReRender();