diff --git a/examples/dashboard/src/DeviceActionsForm.tsx b/examples/dashboard/src/DeviceActionsForm.tsx
index c2c39c0..871d704 100644
--- a/examples/dashboard/src/DeviceActionsForm.tsx
+++ b/examples/dashboard/src/DeviceActionsForm.tsx
@@ -15,13 +15,28 @@ function findClosest(arr: number[], target: number): number {
     );
 }
 
-function getDefaultActionValue(action: DeviceTypeAction): number {
-    if (action.d !== undefined) {
-        return action.d;
+// Map keys in display order: numeric keys (e.g. rates) ascending, label keys (e.g. "raw", "on") as listed
+function getMapKeys(map: Record<string, unknown>): string[] {
+    const keys = Object.keys(map);
+    const allNumeric = keys.every((key) => key.trim() !== '' && Number.isFinite(Number(key)));
+    return allNumeric ? keys.sort((a, b) => Number(a) - Number(b)) : keys;
+}
+
+// The map key selected by default: the one matching d, else the first
+function getDefaultMapKey(action: DeviceTypeAction): string {
+    const mapKeys = action.map ? getMapKeys(action.map) : [];
+    if (action.d !== undefined && mapKeys.includes(String(action.d))) {
+        return String(action.d);
     }
+    return mapKeys[0] ?? '';
+}
+
+function getDefaultActionValue(action: DeviceTypeAction): number | string {
     if (action.map) {
-        const firstMapKey = Object.keys(action.map).sort((a, b) => parseFloat(a) - parseFloat(b))[0];
-        return firstMapKey !== undefined ? parseFloat(firstMapKey) : 0;
+        return getDefaultMapKey(action);
+    }
+    if (action.d !== undefined) {
+        return action.d;
     }
     if (action.r && action.r.length > 1) {
         return (action.r[1] + action.r[0]) / 2;
@@ -33,8 +48,9 @@ type DeviceActionsTableProps = {
     deviceKey: string;
 };
 
+// A number for a value action, the map key for an action with a map
 interface InputValues {
-    [key: string]: number;
+    [key: string]: number | string;
 }
 
 const DeviceActionsForm: React.FC<DeviceActionsTableProps> = ({ deviceKey }: DeviceActionsTableProps) => {
@@ -104,7 +120,7 @@ const DeviceActionsForm: React.FC<DeviceActionsTableProps> = ({ deviceKey }: Dev
                                 }
                             }
                             if (bestKey) {
-                                initialValues['_conf.rate'] = parseFloat(bestKey);
+                                initialValues['_conf.rate'] = bestKey;
                             }
                         } else {
                             // For generic rate dropdown: find closest option
@@ -120,22 +136,22 @@ const DeviceActionsForm: React.FC<DeviceActionsTableProps> = ({ deviceKey }: Dev
         }, 1000);
     }, [deviceKey]);
 
-    const handleInputChange = (name: string, value: number) => {
+    const handleInputChange = (name: string, value: number | string) => {
         setInputValues((prevValues: any) => ({
             ...prevValues,
             [name]: value,
         }));
     };
 
-    const handleSendAction = async (action: DeviceTypeAction, value: number) => {
-        // Send action to device
-        if (!deviceManager || !Number.isFinite(value)) {
+    const handleSendAction = async (action: DeviceTypeAction, value: number | string) => {
+        // Send action to device - a map action sends its key, any other action a number
+        if (!deviceManager || (typeof value === 'number' ? !Number.isFinite(value) : value === '')) {
             return;
         }
         // For _conf.rate actions, use setSampleRate for coordinated polling config
         if (action.n === '_conf.rate' && action.map) {
             setActionStatus('Setting sample rate...');
-            const result = await deviceManager.setSampleRate(deviceKey, value);
+            const result = await deviceManager.setSampleRate(deviceKey, Number(value));
             if (result.ok) {
                 setActionStatus(`Rate: ${result.actualRateHz} Hz, poll: ${result.intervalUs} µs, buf: ${result.numSamples}`);
             } else {
@@ -191,27 +207,22 @@ const DeviceActionsForm: React.FC<DeviceActionsTableProps> = ({ deviceKey }: Dev
                                 </tr>
                             );
                         } else if (action.map) {
-                            const mapKeys = Object.keys(action.map).sort((a, b) => parseFloat(a) - parseFloat(b));
+                            const mapKeys = getMapKeys(action.map);
                             // Label: "Rate Hz" for _conf.rate, the description for other _conf.* settings (their names
                             // aren't readable), otherwise the action name - the description is shown on hover
                             const actionLabel = action.n === '_conf.rate' ? 'Rate Hz' :
                                 (action.n.startsWith('_conf.') ? (action.desc ?? action.n) : action.n);
-                            const actionValue = inputValues[action.n] ?? getDefaultActionValue(action);
+                            const actionValue = String(inputValues[action.n] ?? getDefaultMapKey(action));
                             return (
                                 <tr key={action.n}>
                                     <td title={action.desc}>{actionLabel}</td>
                                     <td>
                                         <select
                                             value={actionValue}
-                                            onChange={(e) =>
-                                                handleInputChange(
-                                                    action.n,
-                                                    parseFloat(e.target.value)
-                                                )
-                                            }
+                                            onChange={(e) => handleInputChange(action.n, e.target.value)}
                                         >
                                             {mapKeys.map((key) => (
-                                                <option key={key} value={parseFloat(key)}>
+                                                <option key={key} value={key}>
                                                     {key}
                                                 </option>
                                             ))}
@@ -232,7 +243,7 @@ const DeviceActionsForm: React.FC<DeviceActionsTableProps> = ({ deviceKey }: Dev
                                 </tr>
                             );
                         } else {
-                            const actionValue = inputValues[action.n] ?? getDefaultActionValue(action);
+                            const actionValue = Number(inputValues[action.n] ?? getDefaultActionValue(action));
                             return (
                                 <tr key={action.n}>
                                     <td title={action.desc}>{action.n}</td>
diff --git a/examples/dashboard/src/SystemTypeMarty/RICStateInfo.ts b/examples/dashboard/src/SystemTypeMarty/RICStateInfo.ts
index 9669e94..827872b 100644
--- a/examples/dashboard/src/SystemTypeMarty/RICStateInfo.ts
+++ b/examples/dashboard/src/SystemTypeMarty/RICStateInfo.ts
@@ -320,7 +320,7 @@ export class RICStateInfo implements RaftDeviceMgrIF {
     }
 
     // Marty ROSSerial devices are read-only in this view
-    async sendAction(_deviceKey: string, _action: DeviceTypeAction, _data: number[]): Promise<boolean> {
+    async sendAction(_deviceKey: string, _action: DeviceTypeAction, _data: Array<number | string>): Promise<boolean> {
         // Not supported for ROSSerial-derived devices
         return false;
     }
diff --git a/package.json b/package.json
index 0cac4fa..f605489 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
     "name": "@robdobsn/raftjs",
-    "version": "2.9.0",
+    "version": "2.9.1",
     "description": "Javascript/TS library for Raft library",
     "main": "dist/web/main.js",
     "types": "dist/web/main.d.ts",
diff --git a/src/RaftDeviceManager.ts b/src/RaftDeviceManager.ts
index 93f6126..cd0a10b 100644
--- a/src/RaftDeviceManager.ts
+++ b/src/RaftDeviceManager.ts
@@ -1457,12 +1457,14 @@ export class DeviceManager implements RaftDeviceMgrIF{
         }
     }
 
-    public async sendAction(deviceKey: string, action: DeviceTypeAction, data: number[]): Promise<boolean> {
+    // For an action with a map, data is one value: the map key (a string such as "raw", or a number for a
+    // numeric key such as "104")
+    public async sendAction(deviceKey: string, action: DeviceTypeAction, data: Array<number | string>): Promise<boolean> {
         console.log(`DeviceManager sendAction ${deviceKey} action ${action.n} data ${data} map ${JSON.stringify(action.map)} keys ${action.map ? Object.keys(action.map) : 'none'}`);
 
-        // For _conf.* actions, delegate to setSampleRate() which coordinates polling params
-        if (action.n.startsWith('_conf.') && action.map && data.length === 1) {
-            const result = await this.setSampleRate(deviceKey, data[0]);
+        // For _conf.rate, delegate to setSampleRate() which coordinates polling params
+        if (action.n === '_conf.rate' && action.map && data.length === 1) {
+            const result = await this.setSampleRate(deviceKey, Number(data[0]));
             return result.ok;
         }
 
@@ -1495,7 +1497,11 @@ export class DeviceManager implements RaftDeviceMgrIF{
                 return false;
             }
         } else {
-            const encoded = encodeActionWrite(action, data);
+            if (data.some((val) => typeof val !== 'number')) {
+                console.warn(`DeviceManager sendAction: action ${action.n} has no map so needs numbers, got ${data}`);
+                return false;
+            }
+            const encoded = encodeActionWrite(action, data as number[]);
             if (encoded === null) {
                 console.warn(`DeviceManager sendAction: can't encode ${data} for action ${action.n}`);
                 return false;
diff --git a/src/RaftDeviceMgrIF.ts b/src/RaftDeviceMgrIF.ts
index 4a8707a..5a6c6e4 100644
--- a/src/RaftDeviceMgrIF.ts
+++ b/src/RaftDeviceMgrIF.ts
@@ -36,7 +36,8 @@ export default interface RaftDeviceMgrIF {
     removeDeviceRemovedCallback(callback: (deviceKey: string, state: DeviceState) => void): void;
 
     // Send action to device
-    sendAction(deviceKey: string, action: DeviceTypeAction, data: number[]): Promise<boolean>;
+    // For an action with a map, data is one value: the map key
+    sendAction(deviceKey: string, action: DeviceTypeAction, data: Array<number | string>): Promise<boolean>;
     sendCompoundAction(deviceKey: string, action: DeviceTypeAction, data: number[][]): Promise<boolean>;
 
     // Raw I2C write + read (returns read bytes, or null if unsupported/failed)