Connection with printer in iOS Application.

Hello guys.
I have got some problem.
My App works with printer Zebra ZQ520. I connected with BLE. When I send some command like
private func writeZebraScript(zpl: String) {
guard let bytes = .utf8), let chars = self.discoverWriteCharacteristic
else {
let error = "Problem with data for zebra script.\nBytes =" +
"\( .utf8) ?? Data())\nCharacteristic = " +
"\(String(describing: self.discoverWriteCharacteristic))\n"

How to make a TCP connection to a ZQ520 from a Javascript iOS app via wifi

I am building an iPhone application using react native and node.js and I need it to be able to print labels via a ZQ520. The LINK-OS MULTIPLATFORM SDK is built for java applications, so my plan is to establish a connection to the printer via wifi and then send instructions formatted in ZPL. I have never worked with anything like this before, so I do not know how to make the initial connection.

In javascript, how do I make a connection from an iOS app to a ZQ520 printer over wifi?

ZSDK_API compiling error

I got problems compiling project with iOS ZSDK it cause this error :

Undefined symbols for architecture armv7:
"_OBJC_CLASS_$_EASession", referenced from:
objc-class-ref in libZSDK_API.a(Zebra_EADSessionController.o)
"_OBJC_CLASS_$_EAAccessoryManager", referenced from:
objc-class-ref in libZSDK_API.a(MfiBtPrinterConnection.o)
ld: symbol(s) not found for architecture armv7
clang: error: linker command failed with exit code 1 (use -v to see invocation)

Issue with response from SGD command “rfid.error.response”

I am using ZD500R printer with my iOS app. I am using SGD rfid.error.response to check for RFID errors happened during printing.
But sometimes instead of expected response mentioned in document , I am getting Host status as response.

Ex: We are getting this in response:
Instead of “RFID OK”

Issue with printer(ZD500R) alerts on iOS

I am using ZD500R printer with my iOS app. I am able to get alerts from printer using TCP/IP connection. But I am facing an intermittent issue where alerts are not coming to app, but printer is still connected to app and I can execute print operations. To solve this issue, I have to restart printer and then it works fine.

Can anyone please guide me or suggest solution to fix this problem.

Please Note: I have used packet sniffing tool as well to check if printer is sending any alert or not. Printer was not sending any alert to specified port and IP address.

Difficulty connecting to ZQ510 over BLE on iOS

Hi, I'm trying to connect my iOS app to a Zebra ZQ510 printer over CoreBluetooth, but not having much luck locating the printer. Looking at the sample code from, I call scanForPeripherals( ) to locate the printer:

central.scanForPeripherals(withServices: services, options: [
CBCentralManagerScanOptionAllowDuplicatesKey : false

PrinterUtil.convertGraphic() in iOS Link-OS SDK


I want to know how I can convert to ZPL from image.
There is SDK function PrinterUtil.convertGraphic() on JAVA, Android SDK.

However I can't find it in iOS SDK.
Is there other function or options If it doesn't support from iOS ? (not store image)

This is because I can't use printer buffer since storeimage() slower than write(), the image placed next label.
I have to check one by one before next label data.

Xamarin Link-os iOS, Doesn't work without data connectivity. ZQ510


I have been working on an app using Xamarin with Link-os plugin and ZQ510 printer. The idea of ​​the app is that it can work in remote places where there is no internet connectivity.

The debug printing process always works. The iPhone can print without any problem with the Wi-Fi off and the data access off.

When the iPhone is disconnected from the PC and has some kind of data access, it is capable of printing. You can even remove the SIM card and connect it to a Wi-Fi without internet access and it will be able to print.