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NuTiny-SDK-N76E003-V2.1 Virtual COM port issues ?

Posted: 26 Apr 2017, 05:56
by jmg
Does anyone have NuTiny-SDK-N76E003-V2.1 Virtual COM working correctly ?

Testing the NuTiny-SDK-N76E003-V2.1, it seems the Virtual COM port has bugs.

I can connect to COM5 using any terminal, but when I run N76E003- UART test code that sends 0x55 continually, characters are lost.
Less than a dozen bytes appear per Port Open.
ie it does open, and some handful of chars appear, but then it fails - no more chars until next open ?
Scope shows the N76E003- UART is burst sending continually, as expected. ie the Nu-Link-Me or Driver, is failing.

Terminal Send from PC also seems to fail, ie Connects ok and Char Counter increments on PC side, but scope probe shows nothing on 76E003.RXD, stays hi

Jumpers on PCB are in COM port side, I think if they are other way, there is no COM port showing.

Q: is this a know issue and do Nuvoton have a fix yet ?

Q: What Terminal Software do Nuvoton use to test the COM port firmware and driver ?

If I connect another USB-UART to the same 76E003 TXD pin, that does show continual received 0x55's, as expected, and of course it does PC -> MCU correctly too.

OS is Win10, 64b
Device manager reports :
Nuvoton virtual COM port (COM5) "This device is working properly."
Driver Date : 17/12/2015
Driver Version : 1.0.0.1

Re: NuTiny-SDK-N76E003-V2.1 Virtual COM port issues ?

Posted: 26 Apr 2017, 16:11
by Lucia
Dear Sir,
Would you mind check with Nu-Link-Me V3.0 side SW3 switch, it connect on the on / off status?
as default this connect to off, means VCOM function is disable. please connect to the on side and confirm with COM port number to confirm it actually connect with for this tiny board.

Re: NuTiny-SDK-N76E003-V2.1 Virtual COM port issues ?

Posted: 26 Apr 2017, 17:31
by jmg
Lucia wrote:
26 Apr 2017, 16:11
Dear Sir,
Would you mind check with Nu-Link-Me V3.0 side SW3 switch, it connect on the on / off status?
as default this connect to off, means VCOM function is disable. please connect to the on side and confirm with COM port number to confirm it actually connect with for this tiny board.
Yes, SW3 is all = ON.
If SW3 = OFF, there is no COM port showing in Device Manager.
The Nuvoton virtual COM port (COM5) does connect, but nothing appears on either of the pins labeled TX, RX and the P1.2 LED I have set to toggle on RX, has no change.

Connection of an external USB-UART bridge, has the P1.2 LED toggle as expected, so N76E003 is correctly programmed.

Appears there is some issue with the COM port firmware, or driver.
Can you give details of the test setup Nuvoton use to confirm Nuvoton virtual COM port actually does work ?
eg Has Nuvoton tested loop-back OK, on Win10.64b Driver ?

Re: NuTiny-SDK-N76E003-V2.1 Virtual COM port issues ?

Posted: 27 Apr 2017, 08:39
by jmg
If anyone has a NuTiny-SDK-N76E003 and a scope/counter, this 2 line BATCH FILE is a very simple COM tester

COM4 is a industry standard USB-UART

Code: Select all

REM  Source:  https://batchloaf.wordpress.com/2013/02/12/simple-trick-for-sending-characters-to-a-serial-port-in-windows/
mode COM4 BAUD=3906 PARITY=n DATA=8
set /p x="UUUU" <nul >\\.\COM4
PAUSE
REM Results:
REM Status for device COM4:
REM -----------------------
REM     Baud:            3906
REM     Parity:          None
REM     Data Bits:       8
REM     Stop Bits:       1
REM     Timeout:         ON
REM     XON/XOFF:        OFF
REM     CTS handshaking: OFF
REM     DSR handshaking: OFF
REM     DSR sensitivity: OFF
REM     DTR circuit:     OFF
REM     RTS circuit:     OFF
REM 
REM 
REM Above has expected 20 edges, from UUUU, so is correct.
REM Pulse Width is  1/0.2558m = 3909.304 Baud, also correct
(for anyone wondering, 3906 Baud is the lowest Baud from N76E003, set for /16/1/Timer1, used to measure the 16MHz HIRC timer with good precision)

and COM5 is Nuvoton virtual COM port

Code: Select all

mode COM5 BAUD=115200 PARITY=n DATA=8
set /p x="UUUU" <nul >\\.\COM5
PAUSE

Rem  Results:
Rem  Status for device COM5:
Rem  -----------------------
Rem      Baud:            115200
Rem      Parity:          None
Rem      Data Bits:       8
Rem      Stop Bits:       1
Rem      Timeout:         ON
Rem      XON/XOFF:        OFF
Rem      CTS handshaking: OFF
Rem      DSR handshaking: OFF
Rem      DSR sensitivity: OFF
Rem      DTR circuit:     OFF
Rem      RTS circuit:     OFF
Rem  
Rem  
Rem  Unlike COM4. NO signals seen ??
Another strange symptom: the NuvoISP.exe does give TXD activity, as it looks for a target with Bootloader installed.
Seems this nearly works ??

Re: NuTiny-SDK-N76E003-V2.1 Virtual COM port issues ?

Posted: 27 Apr 2017, 13:22
by Lucia
Would you mind setup the nuvoton USB driver again to test ? tks.
Nu-Link_USB_Driver_V1.2
http://www.nuvoton.com/hq/resource-down ... 0729202535

Re: NuTiny-SDK-N76E003-V2.1 Virtual COM port issues ?

Posted: 27 Apr 2017, 16:55
by jmg
Trying now, strange, the earlier one I used has the same name, but different size zip ??
Nu-Link_USB_Driver_V1.2.exe.zip = 14,513k, the link above was only Nu-Link_USB_Driver_V1.2.exe.zip = 14,216k and fails to unzip, (looks corrupted?) so I try 2nd download, but that is slow....

2nd time it is 14,513k, and says updated, but exactly the same issues.
Port shows as being open, but no bytes come out when using the BATCH file. Bytes do come out when using the NuvoISP.exe
Looks like there is a bug in the driver, that requires something the ISP code does, that BATCH and Terminal Software, does not do.
This should work, and is easy to test :

Code: Select all

mode COM5 BAUD=115200 PARITY=n DATA=8
set /p x="UUUU" <nul >\\.\COM5