diff --git a/ServerSerial.d.ts b/ServerSerial.d.ts
new file mode 100644
index 0000000..874e6c8
--- /dev/null
+++ b/ServerSerial.d.ts
@@ -0,0 +1,21 @@
+import * as events from 'events';
+import { SerialPortOpenOptions } from "serialport"
+import { FCallback, IServiceVector } from './ServerTCP';
+import { ErrorCallback } from '@serialport/stream';
+
+export class ServerSerial extends events.EventEmitter {
+    constructor(vector: IServiceVector, options: IServerSerialOptions);
+    close(cb: FCallback): void;
+}
+
+type IServerSerialOptions = SerialPortOpenOptions<any> & {
+    debug?: boolean,
+    unitID?: number,
+    openCallback?: ErrorCallback
+}
+
+export declare interface ServerSerial {
+    on(event: 'socketError', listener: FCallback): this;
+    on(event: 'error', listener: FCallback): this;
+    on(event: 'initialized', listener: FCallback): this;
+}
diff --git a/ServerTCP.d.ts b/ServerTCP.d.ts
index 64b411c..1d86f55 100644
--- a/ServerTCP.d.ts
+++ b/ServerTCP.d.ts
@@ -5,7 +5,7 @@ export class ServerTCP extends events.EventEmitter {
     close(cb: FCallback): void;
 }
 
-interface IServiceVector {
+export interface IServiceVector {
     getCoil?:
         ((addr: number, unitID: number, cb: FCallbackVal<boolean>) => void) |
         ((addr: number, unitID: number) => Promise<boolean>) |
@@ -58,5 +58,5 @@ export declare interface ServerTCP {
     on(event: 'initialized', listener: FCallback): this;
 }
 
-type FCallbackVal<T> = (err: Error | null, value: T) => void;
-type FCallback = (err: Error | null) => void;
+export type FCallbackVal<T> = (err: Error | null, value: T) => void;
+export type FCallback = (err: Error | null) => void;
diff --git a/index.d.ts b/index.d.ts
index d29be8f..f88a711 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,4 +1,5 @@
 import {ModbusRTU} from "./ModbusRTU";
 export * from "./ServerTCP";
+export * from "./ServerSerial";
 
 export default ModbusRTU;
\ No newline at end of file
diff --git a/servers/serverserial.js b/servers/serverserial.js
index 81ca1c1..e49b48d 100644
--- a/servers/serverserial.js
+++ b/servers/serverserial.js
@@ -237,7 +237,7 @@ class ServerSerial extends EventEmitter {
         const optionsWithBindingandSerialport = Object.assign({}, serialportOptions, optionsWithBinding);
 
         // create a serial server
-        modbus._serverPath = new SerialPort(optionsWithBindingandSerialport);
+        modbus._serverPath = new SerialPort(optionsWithBindingandSerialport, options.openCallback);
 
         // create a serial server with a timeout parser
         modbus._server = modbus._serverPath.pipe(new ServerSerialPipeHandler(optionsWithSerialPortTimeoutParser));
@@ -253,7 +253,7 @@ class ServerSerial extends EventEmitter {
         // remember open sockets
         modbus.socks = new Map();
 
-        modbus._server.on("open", function() {
+        modbus._serverPath.on("open", function() {
             modbus.socks.set(modbus._server, 0);
 
             modbusSerialDebug({
@@ -270,6 +270,7 @@ class ServerSerial extends EventEmitter {
                 modbus.socks.delete(modbus._server);
             });
 
+            modbus.emit("initialized");
         });
 
         modbus._server.on("data", function(data) {