run failure "OPC-LED-BUTTON-SERVER.XLUA"

[keith61157]

I have xedge32 flashed to an ESP32-S3 chip. I am able to run the "first project" example without issue.

When I try to build a OPC UA server by copying the "OPC-LED-BUTTON-SERVER.XLUA" example code into a Lua app and run I get the following run failure:

Xedge: Running /spiflash/3SERVER/3SERVER.xlua failed:
3SERVER.xlua:4: attempt to call a nil value (field 'newServer')
stack traceback:
3SERVER.xlua:4: in main chunk
[C]: in function 'xpcall'
.lua/xedge.lua:331: in upvalue 'loadAndRunLua'
.lua/xedge.lua:378: in upvalue 'manageXLuaFile'
.lua/xedge.lua:554: in function <.lua/xedge.lua:548>

When I try to just import the libraries and build and initialize a server to trouble shoot with the following code:

local ua = require("opcua.api")
-- Create new OPC UA server instance.
-- Pass configuration table to server.
local server = ua.newServer()
-- Initialize server.
server:initialize()

I get the same run failure. I can load the opcua.api and create server function "ua.newServer()" but once I add the server intialize function I get the run failure.

Any guidance regarding what I am doing wrong would be appreciated.

Thank you,

Keith

[arykovanov]

Hello Keith,

Could you please share the steps you followed to build the XEdge platform?
It seems that OPC UA needs to be enabled in two different places, and I’d like to confirm that my procedure matches yours.

Here are the steps I used:

git clone --recursive --recurse-submodules https://github.com/RealTimeLogic/xedge32.git xedge
cd xedge
git submodule update --init --remote

Run the build script and enable OPC UA when prompted:

./BuildESP32ResourceFile.sh
Do you want to include OPC-UA (y/n)? y

Configure the ESP-IDF project:

source ~/esp-idf/export.sh
idf.py set-target esp32s3
idf.py menuconfig

In XEdge Config → OPC UA, enable OPC UA.

Then build and flash the firmware:

idf.py build flash monitor

Enable the blinked application and add the following Lua source file (opcua.xlua):

trace("Loading OPCUA API")

local ua = require("opcua.api")

trace("Creating OPCUA server")
local server = ua.newServer()

trace("Initializing OPCUA server")
server:initialize()

trace("Running OPCUA server")
server:run()
trace("OPC UA Server ready")

function onunload()
  trace("Stopping OPCUA server")
  server:shutdown()
end

These steps worked for me.
Please try them again and share your results.

Thanks!
Alexander.

[keith61157]

Hello Alexander, I have built the Xedge32 platform on a Windows 10 OS. I did the auto install (see below) and also used the Espressif Flasher. Both methods are outlined in the Real Time Logic documentation regarding loading the Xedge32 platform on an ESP32-S3 system. In this instance I am not offered the option to include or exclude OPC-UA. Can you please walk me through how to check if the OPC-UA libraries are part of the instance I loaded using Windows syntax?  Also, how would I add the OPC-UA libraries to an existing Windows instance that was configured using the Real Time Logic instructions? I am proficient using the Espressif Flasher if you can give me some guidance on what code to load and the address to use. I am new to this and a novice at Linux. But, willing to learn if you have the patience to guide me please. Thank you, Keith  On Monday, November 10, 2025 at 04:36:28 AM CST, Alexander Rykovanov ***@***.***> wrote: arykovanov left a comment (RealTimeLogic/OPC-UA-Examples#12) Hello Keith! Can you share your steps, how you build XEdge platform? It is required to enable OPCUA in two places. Here are my steps: - git clone --recursive --recurse-submodules https://github.com/RealTimeLogic/xedge32.git xedge cd xedge git submodule update --init --remote - Run and enable OPCUA ./BuildESP32ResourceFile.sh Building Xedge32 resource file main/BAS/examples/xedge/obj/XedgeZip.c ~/src/realtimelogic/ua_error/main/BAS-Resources/build ~/src/realtimelogic/ua_error Running /home/arykovanov/src/realtimelogic/ua_error/main/BAS-Resources/build/Xedge.sh Do you want to include OPC-UA (y/n)? y - source ~/esp-idf/export.sh - idf.py set target esp32s3 - idf.py menuconfig Enable OPCUA in the section XEdge config-> OPC UA. Enable OPC UA - idf.py build flash monitor - add source file opcua.xlua: trace"Loading opcua api"

…

-- Load the OPCUA API local ua = require("opcua.api") trace"Creating opcua server" local server = ua.newServer() trace("Initialize opcua server") server:initialize() trace("Run opcua server") server:run() trace("OPCUA Server ready")

-- The following function is called when the application is stopped. function onunload() trace("Stopping OPCUA server") -- Shutdown the server. This will stop the server and close all connections. server:shutdown() end — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[surfskidude]

• idf.py menuconfig -> Xedge config -> OPC UA -> Enable

[arykovanov]

I repeated the steps from the page: https://realtimelogic.com/ba/ESP32/source/GettingStarted.html#firmware-option-1-use-pre-compiled-firmware

My device model is the ESP32-S3-WROOM-1, with 16MB flash and 8MB RAM.

Using an Espressif flash tool I downloaded file merged-xedge-s0.bin at 0 address.

Then connected ESP32 to wi-fi. Eventually it was possible to run OPCUA server on a XEdge IDE.

What device do you use?
Can you share boot log to see parameters of the device at runtime? It is possible to select text in Putty (for example) or create a snapshot.

In the first message the error

3SERVER.xlua:4: attempt to call a nil value (field 'newServer'

says that local variable 'ua' is a table, but has no function 'newServer'.

Can you run the following code to print out content of the 'ua' table?

 trace("import opcua")
local ua = require("opcua.api")
trace(ua)
if ua then
    for k,v in pairs(ua) do
      trace(k, v)
    end
end

I have the following output:

[keith61157]

Hello Alexander, Thank you so much for the reply and information. I will send a boot log, I just got in from work so it will probably be tomorrow. I will also run the code below and give you my results. I am using an ESP32-S3 N16R8.  I really appreciate the help :). Thank you, Keith On Monday, November 10, 2025 at 01:08:02 PM CST, Alexander Rykovanov ***@***.***> wrote: arykovanov left a comment (RealTimeLogic/OPC-UA-Examples#12) I repeated the steps from the page: https://realtimelogic.com/ba/ESP32/source/GettingStarted.html#firmware-option-1-use-pre-compiled-firmware Using an Espressif flash tool I downloaded file merged-xedge-s0.bin at 0 address. Then connected ESP32 to wi-fi eventually it was possible to run OPCUA server. What device do you use? Can you share boot log to see parameters of the device at runtime? It is possible to select text in Putty (for example) or create a snapshot. In the first message the error 3SERVER.xlua:4: attempt to call a nil value (field 'newServer' says that local variable 'ua' is a table, but has no function 'newServer'. Can you run the following code to print content of the 'ua' vairable? trace("import opcua") local ua = require("opcua.api") trace(ua) if ua then for k,v in pairs(ua) do trace(k, v) end end I have the following output: image.png (view on web) — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[keith61157]

Hello Alexander, Bootlog attached as well as chip info from the flasher.  Are you saying I should flash merged-xedge-s0.bin at address 0x0. No bootoader is needed?  I am not sure what the automatic flasher puts on the chip but I sent you a screenshot of what I flashed last time I did this manually. This is what I was using to try and start the server. Then out of desperation reflashed using the automatic method. Again, thank you very much for your help. Keith On Monday, November 10, 2025 at 07:49:51 PM CST, Keith Mildenberger ***@***.***> wrote: Hello Alexander, Thank you so much for the reply and information. I will send a boot log, I just got in from work so it will probably be tomorrow. I will also run the code below and give you my results. I am using an ESP32-S3 N16R8.  I really appreciate the help :). Thank you, Keith On Monday, November 10, 2025 at 01:08:02 PM CST, Alexander Rykovanov ***@***.***> wrote: arykovanov left a comment (RealTimeLogic/OPC-UA-Examples#12) I repeated the steps from the page: https://realtimelogic.com/ba/ESP32/source/GettingStarted.html#firmware-option-1-use-pre-compiled-firmware Using an Espressif flash tool I downloaded file merged-xedge-s0.bin at 0 address. Then connected ESP32 to wi-fi eventually it was possible to run OPCUA server. What device do you use? Can you share boot log to see parameters of the device at runtime? It is possible to select text in Putty (for example) or create a snapshot. In the first message the error 3SERVER.xlua:4: attempt to call a nil value (field 'newServer' says that local variable 'ua' is a table, but has no function 'newServer'. Can you run the following code to print content of the 'ua' vairable? trace("import opcua") local ua = require("opcua.api") trace(ua) if ua then for k,v in pairs(ua) do trace(k, v) end end I have the following output: image.png (view on web) — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***> ESP-ROM:esp32s3-20210327 Build:Mar 27 2021 rst:0x1 (POWERON),boot:0x8 (SPI_FAST_FLASH_BOOT) SPIWP:0xee mode:DIO, clock div:1 load:0x3fce2810,len:0x15a0 load:0x403c8700,len:0x4 load:0x403c8704,len:0xd20 load:0x403cb700,len:0x2ee4 entry 0x403c8928 I (27) boot: ESP-IDF v5.4 2nd stage bootloader I (27) boot: compile time Mar 5 2025 08:21:20 I (27) boot: Multicore bootloader I (27) boot: chip revision: v0.2 I (30) boot: efuse block revision: v1.3 I (33) boot.esp32s3: Boot SPI Speed : 80MHz I (37) boot.esp32s3: SPI Mode : DIO I (41) boot.esp32s3: SPI Flash Size : 8MB I (45) boot: Enabling RNG early entropy source... I (49) boot: Partition Table: I (52) boot: ## Label Usage Type ST Offset Length I (58) boot: 0 nvs WiFi data 01 02 00009000 00006000 I (65) boot: 1 otadata OTA data 01 00 0000f000 00002000 I (71) boot: 2 phy_init RF data 01 01 00011000 00001000 I (78) boot: 3 ota_0 OTA app 00 10 00020000 00310000 I (84) boot: 4 ota_1 OTA app 00 11 00330000 00310000 I (91) boot: 5 storage Unknown data 01 81 00640000 001b5000 I (97) boot: 6 xcfg Unknown data 01 81 007f5000 00008000 I (104) boot: End of partition table I (107) esp_image: segment 0: paddr=00020020 vaddr=3c150020 size=b91cch (758220) map I (248) esp_image: segment 1: paddr=000d91f4 vaddr=3fca2200 size=0621ch ( 25116) load I (253) esp_image: segment 2: paddr=000df418 vaddr=40374000 size=00c00h ( 3072) load I (255) esp_image: segment 3: paddr=000e0020 vaddr=42000020 size=142890h (1321104) map I (492) esp_image: segment 4: paddr=002228b8 vaddr=40374c00 size=1d560h (120160) load I (519) esp_image: segment 5: paddr=0023fe20 vaddr=600fe100 size=0001ch ( 28) load I (531) boot: Loaded app from partition at offset 0x20000 I (531) boot: Disabling RNG early entropy source... I (541) octal_psram: vendor id : 0x0d (AP) I (541) octal_psram: dev id : 0x02 (generation 3) I (541) octal_psram: density : 0x03 (64 Mbit) I (543) octal_psram: good-die : 0x01 (Pass) I (547) octal_psram: Latency : 0x01 (Fixed) I (552) octal_psram: VCC : 0x01 (3V) I (556) octal_psram: SRF : 0x01 (Fast Refresh) I (561) octal_psram: BurstType : 0x01 (Hybrid Wrap) I (566) octal_psram: BurstLen : 0x01 (32 Byte) I (570) octal_psram: Readlatency : 0x02 (10 ***@***.***) I (575) octal_psram: DriveStrength: 0x00 (1/1) I (580) MSPI Timing: PSRAM timing tuning index: 5 I (584) esp_psram: Found 8MB PSRAM device I (588) esp_psram: Speed: 80MHz I (591) cpu_start: Multicore app

[keith61157]

Hello Alexander, Reflashed merged-xedge-s0.bin at 0x0 as you suggested. See new bootlog, attached, looks as it should. I somehow overlooked this in the instructions and used method 2, the three file approach. Was able to get Wifi running nd connected to the xedge32 IDE. Started the server in the Lua Shell and no hate mail, see attached after boot log. Will build an app tomorrow with the server code and see how that goes. Then will try to get Ignition to connect if the sever builds ok. I will keep you posted and thank you. Keith On Monday, November 10, 2025 at 08:47:37 PM CST, Keith Mildenberger ***@***.***> wrote: Hello Alexander, Bootlog attached as well as chip info from the flasher.  Are you saying I should flash merged-xedge-s0.bin at address 0x0. No bootoader is needed?  I am not sure what the automatic flasher puts on the chip but I sent you a screenshot of what I flashed last time I did this manually. This is what I was using to try and start the server. Then out of desperation reflashed using the automatic method. Again, thank you very much for your help. Keith On Monday, November 10, 2025 at 07:49:51 PM CST, Keith Mildenberger ***@***.***> wrote: Hello Alexander, Thank you so much for the reply and information. I will send a boot log, I just got in from work so it will probably be tomorrow. I will also run the code below and give you my results. I am using an ESP32-S3 N16R8.  I really appreciate the help :). Thank you, Keith On Monday, November 10, 2025 at 01:08:02 PM CST, Alexander Rykovanov ***@***.***> wrote: arykovanov left a comment (RealTimeLogic/OPC-UA-Examples#12) I repeated the steps from the page: https://realtimelogic.com/ba/ESP32/source/GettingStarted.html#firmware-option-1-use-pre-compiled-firmware Using an Espressif flash tool I downloaded file merged-xedge-s0.bin at 0 address. Then connected ESP32 to wi-fi eventually it was possible to run OPCUA server. What device do you use? Can you share boot log to see parameters of the device at runtime? It is possible to select text in Putty (for example) or create a snapshot. In the first message the error 3SERVER.xlua:4: attempt to call a nil value (field 'newServer' says that local variable 'ua' is a table, but has no function 'newServer'. Can you run the following code to print content of the 'ua' vairable? trace("import opcua") local ua = require("opcua.api") trace(ua) if ua then for k,v in pairs(ua) do trace(k, v) end end I have the following output: image.png (view on web) — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>

[arykovanov]

Hello Keith,
How’s it going? Have you had a chance to try running the server?

[keith61157]

Hello Alexander, Finally broke through thanks to you help. See below, "ESP32 XEDGE32" OPC UA Connection up and running. The automatic flash and several of the other Real Time Logic bin files apparently do not included the OPCUA API libraries. All I had to do was flash the "merged-xedge-s0.bin" file and I could run the server. Now on to running your project. I work at Target and am a Senior System Engineer. We currently use Ignition for all of our SCADA. I work in the Global Supply Chain division and we use conveyors, scanner and automated sortation systems to move large volumes of packages and freight. My interest in using ESP32 devices is gathering situational data on equipment performance. For example, motors, VFD and various other sensors we use. The instrumentation from the OEMs for many of the edge devices we have is good but, there are some gaps I want to fill. ESP32 gives me a cost effective and flexible method to do this. Lua is the only method I could find that would allow me to build an OPCUA server that would integrate into Ignition. New to Lua but finding that it may be very useful to me over the long haul. So, will keep learning. I will keep in touch and share what we develop here. Again, thank you so much for the help. I was very stuck. Keith On Thursday, November 13, 2025 at 11:06:31 PM CST, Alexander Rykovanov ***@***.***> wrote: arykovanov left a comment (RealTimeLogic/OPC-UA-Examples#12) Hello Keith, How’s it going? Have you had a chance to try running the server? — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>