diff --git a/src/main/java/org/mobidgim/mobidigimproject/service/SettingService.java b/src/main/java/org/mobidgim/mobidigimproject/service/SettingService.java
index 9bea2c9..475b0bf 100644
--- a/src/main/java/org/mobidgim/mobidigimproject/service/SettingService.java
+++ b/src/main/java/org/mobidgim/mobidigimproject/service/SettingService.java
@@ -97,7 +97,7 @@ public class SettingService {
         if (request.getProtocol() != Protocol.OPC_UA) request.setOPC_UA(null);
         if (request.getProtocol() != Protocol.MODBUS) request.setMODBUS(null);
         if (request.getCanInput() != CanInput.ON) request.setCAN(null);
-        if (!"on".equalsIgnoreCase(request.getOdoMeter())) {
+        if (!"on".equalsIgnoreCase(request.getOdoOn())) {
             request.setOdometerSpeed(null);
             request.setOdometerDir(null);
         }
diff --git a/src/main/resources/static/js/navigation.js b/src/main/resources/static/js/navigation.js
index b830fca..e3e9483 100644
--- a/src/main/resources/static/js/navigation.js
+++ b/src/main/resources/static/js/navigation.js
@@ -19,7 +19,7 @@ export function createNavigation() {
     const topbarProtocolActions = document.querySelector('.topbar-protocol-actions');
     const protocolSelect = byId('reg_protocol');
     const canInputSelect = byId('reg_can_input');
-    const odometerSelect = byId('OdoMeter');
+    const odometerSelect = byId('odo_on');
 
     function showPage(pageName) {
         Object.values(pages).forEach((page) => {
diff --git a/src/main/resources/static/js/protocol/odometer.js b/src/main/resources/static/js/protocol/odometer.js
index 00d33c8..d876e56 100644
--- a/src/main/resources/static/js/protocol/odometer.js
+++ b/src/main/resources/static/js/protocol/odometer.js
@@ -2,14 +2,15 @@ import { byId } from '../utils/dom.js';
 
 function buildRow(target, data = {}) {
     const safeData = data && typeof data === 'object' ? data : {};
+    const sourceValue = safeData.source ?? safeData.odo_speed_source ?? '';
 
     return `
         <tr class="odometer-row" data-target="${target}">
             <td>${target}</td>
             <td>
                 <select class="odometer-source-input">
-                    <option value="can" ${safeData.odo_speed_source === 'can' ? 'selected' : ''}>can</option>
-                    <option value="hw" ${safeData.odo_speed_source === 'hw' ? 'selected' : ''}>hw</option>
+                    <option value="can" ${sourceValue === 'can' ? 'selected' : ''}>can</option>
+                    <option value="hw" ${sourceValue === 'hw' ? 'selected' : ''}>hw</option>
                 </select>
             </td>
             <td><input class="odometer-id-input" value="${safeData.id ?? ''}"></td>
@@ -39,7 +40,7 @@ export function createOdometerController() {
         }
 
         return {
-            odo_speed_source: row.querySelector('.odometer-source-input')?.value?.trim() ?? '',
+            source: row.querySelector('.odometer-source-input')?.value?.trim() ?? '',
             id: row.querySelector('.odometer-id-input')?.value?.trim() ?? '',
             shift: row.querySelector('.odometer-shift-input')?.value?.trim() ?? '',
             expr: row.querySelector('.odometer-expr-input')?.value?.trim() ?? '',
diff --git a/src/main/resources/static/js/protocol/protocolData.js b/src/main/resources/static/js/protocol/protocolData.js
index 5ec435e..4a35720 100644
--- a/src/main/resources/static/js/protocol/protocolData.js
+++ b/src/main/resources/static/js/protocol/protocolData.js
@@ -4,7 +4,26 @@ import { byId } from '../utils/dom.js';
 export const normProtocol = (value) => String(value ?? '').trim().replace(/[-\s]+/g, '_').toUpperCase();
 export const getOpcArr = (data) => data?.OPC_UA ?? data?.['OPC-UA'] ?? [];
 
-const checkboxIds = ['ai0', 'ai1', 'ai2', 'ai3', 'di0', 'di1', 'di2', 'di3'];
+function normalizeLegacyOdometerKeys(register) {
+    if (!register || typeof register !== 'object') {
+        return register;
+    }
+
+    if (register.OdoMeter !== undefined && register.odo_on === undefined) {
+        register.odo_on = register.OdoMeter;
+    }
+
+    if (register.odo_Meter !== undefined && register.odo_on === undefined) {
+        register.odo_on = register.odo_Meter;
+    }
+
+    delete register.OdoMeter;
+    delete register.odo_Meter;
+
+    return register;
+}
+
+const checkboxIds = ['ai0', 'ai1', 'di0', 'di1'];
 const toLower = (value) => String(value ?? '').trim().toLowerCase();
 const toUpper = (value) => String(value ?? '').trim().toUpperCase();
 
@@ -31,7 +50,7 @@ function normalizeValueForElement(htmlId, value) {
         return normProtocol(value);
     case 'reg_can_input':
     case 'reg_dr_on_off':
-    case 'OdoMeter':
+    case 'odo_on':
     case 'reg_two_byte_order':
         return toLower(value);
     case 'reg_four_byte_order':
@@ -46,7 +65,7 @@ function normalizeValueForElement(htmlId, value) {
 }
 
 export function normalizeRegisterForPost(register) {
-    const normalized = JSON.parse(JSON.stringify(register || {}));
+    const normalized = normalizeLegacyOdometerKeys(JSON.parse(JSON.stringify(register || {})));
     const toUpperSnake = (value) => String(value ?? '').trim().toUpperCase().replace(/[-\s]+/g, '_');
 
     if (normalized.protocol) {
@@ -57,12 +76,8 @@ export function normalizeRegisterForPost(register) {
         normalized.can_input = String(normalized.can_input).trim().toUpperCase();
     }
 
-    if (normalized.OdoMeter) {
-        normalized.OdoMeter = String(normalized.OdoMeter).trim().toLowerCase();
-    }
-
-    if (normalized.odo_Meter) {
-        normalized.odo_Meter = String(normalized.odo_Meter).trim().toLowerCase();
+    if (normalized.odo_on) {
+        normalized.odo_on = String(normalized.odo_on).trim().toLowerCase();
     }
 
     if (normalized.MEID !== undefined && normalized.MEID !== null) {
@@ -100,7 +115,7 @@ export function createProtocolDataController({
     const protocolSelect = byId('reg_protocol');
     const canInputSelect = byId('reg_can_input');
     const drOnOffSelect = byId('reg_dr_on_off');
-    const odometerSelect = byId('OdoMeter');
+    const odometerSelect = byId('odo_on');
 
     function syncProtocolMenus() {
         navigation.toggleProtocolMenus(protocolSelect?.value, canInputSelect?.value, odometerSelect?.value);
@@ -137,7 +152,7 @@ export function createProtocolDataController({
     }
 
     function collectProtocolData() {
-        const register = getLastLoadedRegisterData();
+        const register = normalizeLegacyOdometerKeys(getLastLoadedRegisterData());
 
         Object.entries(REGISTER_ID_MAP).forEach(([htmlId, dtoKey]) => {
             const element = byId(htmlId);
@@ -160,10 +175,10 @@ export function createProtocolDataController({
         const odometerData = odometerController.collectData();
 
         if (toLower(register.dr_on) !== 'on') {
-            register.odo_Meter = 'off';
+            register.odo_on = 'off';
             register.odo_speed = null;
             register.odo_direction = null;
-        } else if (String(register.odo_Meter ?? '').toLowerCase() === 'on') {
+        } else if (String((register.odo_on ?? register.odo_Meter) ?? '').toLowerCase() === 'on') {
             register.odo_speed = odometerData.odo_speed;
             register.odo_direction = odometerData.odo_direction;
         } else {
@@ -171,6 +186,7 @@ export function createProtocolDataController({
             register.odo_direction = null;
         }
 
+        normalizeLegacyOdometerKeys(register);
         return register;
     }
 
@@ -179,7 +195,9 @@ export function createProtocolDataController({
             return;
         }
 
-        setLastLoadedRegisterData(register);
+        const normalizedRegister = normalizeLegacyOdometerKeys({ ...register });
+
+        setLastLoadedRegisterData(normalizedRegister);
 
         Object.entries(REGISTER_ID_MAP).forEach(([htmlId, dtoKey]) => {
             const element = byId(htmlId);
@@ -187,8 +205,8 @@ export function createProtocolDataController({
                 return;
             }
 
-            if (Object.prototype.hasOwnProperty.call(register, dtoKey)) {
-                const value = register[dtoKey];
+            if (Object.prototype.hasOwnProperty.call(normalizedRegister, dtoKey)) {
+                const value = normalizedRegister[dtoKey];
                 if (element.type === 'checkbox') {
                     element.checked = value === '1' || value === true;
                 } else {
@@ -207,22 +225,22 @@ export function createProtocolDataController({
         checkboxIds.forEach((id) => {
             const checkbox = byId(id);
             if (checkbox) {
-                checkbox.checked = register[id] === '1' || register[id] === true;
+                checkbox.checked = normalizedRegister[id] === '1' || normalizedRegister[id] === true;
             }
         });
 
-        if (register.protocol && protocolSelect) {
-            const protocol = normProtocol(register.protocol);
+        if (normalizedRegister.protocol && protocolSelect) {
+            const protocol = normProtocol(normalizedRegister.protocol);
             protocolSelect.value = protocol;
-            setLastLoadedRegisterData({ ...register, protocol });
+            setLastLoadedRegisterData({ ...normalizedRegister, protocol });
         }
 
-        modbusController.renderRows(Array.isArray(register.MODBUS) ? register.MODBUS : []);
-        opcUaController.renderRows(Array.isArray(getOpcArr(register)) ? getOpcArr(register) : []);
-        canController.renderRows(Array.isArray(register.CAN) ? register.CAN : []);
+        modbusController.renderRows(Array.isArray(normalizedRegister.MODBUS) ? normalizedRegister.MODBUS : []);
+        opcUaController.renderRows(Array.isArray(getOpcArr(normalizedRegister)) ? getOpcArr(normalizedRegister) : []);
+        canController.renderRows(Array.isArray(normalizedRegister.CAN) ? normalizedRegister.CAN : []);
         odometerController.renderRows({
-            odo_speed: register.odo_speed ?? null,
-            odo_direction: register.odo_direction ?? null,
+            odo_speed: normalizedRegister.odo_speed ?? null,
+            odo_direction: normalizedRegister.odo_direction ?? null,
         });
         syncOdometerAvailability();
         syncProtocolMenusDeferred();
diff --git a/src/main/resources/static/js/protocol/protocolValidation.js b/src/main/resources/static/js/protocol/protocolValidation.js
index 8577ebf..e7bb0b5 100644
--- a/src/main/resources/static/js/protocol/protocolValidation.js
+++ b/src/main/resources/static/js/protocol/protocolValidation.js
@@ -30,7 +30,7 @@ export function getRegisterConfigValidationError(data) {
     }
 
     if (String(data.dr_on ?? '').toLowerCase() !== 'on' && String(data.odo_on ?? '').toLowerCase() === 'on') {
-        return "'odo_Meter' cannot be on when 'dr_on' is off.";
+        return "'odo_on' cannot be on when 'dr_on' is off.";
     }
 
     if (data.protocol === 'MODBUS') {
@@ -82,13 +82,13 @@ export function getRegisterConfigValidationError(data) {
         const direction = data.odo_direction;
 
         for (const [label, item] of [['odo_speed', speed], ['odo_direction', direction]]) {
-            if (!hasAnyValue(item, ['odo_speed_source', 'id', 'shift', 'expr', 'mask'])) {
+            if (!hasAnyValue(item, ['source', 'odo_speed_source', 'id', 'shift', 'expr', 'mask'])) {
                 continue;
             }
 
-            const source = String(item?.odo_speed_source ?? '').trim().toLowerCase();
+            const source = String(item?.source ?? item?.odo_speed_source ?? '').trim().toLowerCase();
             if (!source) {
-                return `${label} missing 'odo_speed_source'.`;
+                return `${label} missing 'source'.`;
             }
 
             if (source === 'can') {