Usb to uart bridge

[brankoil]

Hello,
I have two boards. One is BTE19-04 board with chip HT42B534 on it, second is BTE17-14 without USB chip, but have BTE18-05 with chip HT as well.
Both boards are recognised by Windows as a " USB TO UART BRIDGE " in the device manager under " Devices with universal ... " . In properties of them it says " device is working properly ".
Arduino does not recognise neither COM port, the button is greyed.
Please advice, thanks.
Branko

[sterretje]

No real idea. Maybe installing the drivers might do the trick.

[sonofcy]

What do you want to do with the boards?

[BitSeeker]

Ugghhh the Holtek UART chip. It is EOL since 2020:

https://www.holtek.com/webapi/168740/EOL_HT42B534-1.pdf

Older Windows drivers can still be found on their website:

https://www.holtek.com/page/vg/HT42B534-2

Not sure whether they work on Win 10 or Win 11 though.

As regards the BTE17-14, there is more info on those here:

My experience with the $1 Pro Mini "clones" (BTE17-14)

I ordered up a few of these ultra-cheap alleged Pro Mini clones to play with. I believe that BTE17-14 is the part / model number but I can't be completely sure as they have other markings as well (see pic). First thing I notice is the lack of precision frequency reference - no crystal or resonator. More on this in a bit. The seller offered a board defs package which I installed - but quickly learned that sketches would not compile when one of the new boards was selected as target. So much for …

Since there is no UART, they require an external method of programming of some sort. I have worked with the LGT8FX boards (with Holtek UART) on Linux, but not the cut down without UART version.

[jim-p]

@brankoil

Arduino does not recognise neither COM port, the button is greyed

If it does not appear under Ports then Arduino won't see it as USB-UART device.
However I'm not sure why it does not appear.

[brankoil]

Upload code from Arduino IDE to Nano/Mini boards ( as BTE boards actuall are ). They have a HT42B534 chip as USB interface .

V pon., 13. jan. 2025, 13:17 je oseba Sonofcy via Arduino Forum <notifications@arduino.discoursemail.com> napisala:

[sonofcy]

I think you need to add this to your additional boards etc.
https://github.com/dbuezas/lgt8fx

[brankoil]

I did, Arduino shows only LGT8F328 board ( and not all LGT boards ).

V pon., 13. jan. 2025, 14:04 je oseba Sonofcy via Arduino Forum <notifications@arduino.discoursemail.com> napisala:

[brankoil]

PS under programer Arduino shows AVR ISP and LGTSWD MK II as ISP.

V pon., 13. jan. 2025, 14:04 je oseba Sonofcy via Arduino Forum <notifications@arduino.discoursemail.com> napisala:

[ptillisch]

Hi @brankoil. Please try installing the driver, as suggested by @BitSeeker in post #4. I'll provide instructions you can follow to do that:

1. Click the following link to open the manufacturer's page of Holtek HT42B534 chip:
   https://www.holtek.com/page/vg/HT42B534-2
2. Select the "Resources" tab on the page.
3. Scroll down the page until you see the "USBBridgeSetup_CA_241210.zip" download link. Click on it.
   Your web browser will start a file download.
4. Wait for the download to finish.
5. Extract the downloaded file to any convenient location on your computer.
6. Connect either of the boards to your computer with a USB cable.
7. Double click on the USBBridgeSetup_CA_241210.exe file from the extracted folder.
   The "Setup - Holtek USB Bridge Installer" will open.
8. Select the "USB to UART Bridge" radio button from the dialog.
9. Click the "Next" button in the dialog.
10. Complete the remaining steps in the dialog.
11. Start Arduino IDE.
12. Open the Tools > Port menu.

Hopefully you will now see the serial port of the board listed under the menu. If so, select it and try an upload.

[brankoil]

Did all that, now Arduino recognises both boards on com7.
Does not upload to any of them, Will try with different clock dividers, hope will help.

V pon., 13. jan. 2025, 16:42 je oseba ptillisch via Arduino Forum <notifications@arduino.discoursemail.com> napisala:

[ptillisch]

@brankoil

now Arduino recognises both boards on com7.

That is great progress!

@brankoil

Will try with different clock dividers, hope will help.

OK, just let us know if you can't find a solution and we'll try to provide further assistance.

[brankoil]

Today's progres: set :
SERIAL_RX_BUFFER_SIZE 250 ( to burn ISP )

• board LGT8F328 + BTE18-05 interface ( has HT42B534B-1 chip )
  programer : AVR ISP.......................... works on all clock div values
  programer : LGTSWDmkII as ISP .....works on all clock div values, except on 32
• board BTE18-04 ( designated with LGT8F328B ;LGT8F32 ; LQFP32 Mini EVB ;
  NANO 3 compatible) with HT42B534-2 on the board
  works with both programers and on any clock div values.

So, the problem is solved, now I can start working on my projects.
Thank you very much.
with best regards, Branko

[ptillisch]

You are welcome. I'm glad they are working now.

Regards, Per