How to use Uart#2 upload files to my NX

I want to use my NX’s Uart#2 upload files to my Nx
X/Y con’t upload files to my Nx.
Z uploading , my Nx will shutdown.
what should i do?

hello 540189861,

may I know the actual use-case, why don’t you setup ethernet and using ssh utility for file copy?

I want to add that I don’t know which UART device would correspond to UART#2. Do you know which device special file that produces? Meaning something similar to “/dev/ttyS#” or “/dev/ttyTHS#” (both can be the same hardware, but one notation is for a different driver than the other).

hello,JerryChang.The working environment of our equipment cannot use the network and SSH. Just use uart#2. However, I found that UART # 2 encountered some problems during the file transfer process, which led to the transfer failure


Hello, Mr linuxdev. Like this? ttyTCU0?

Sorry I forgot to explain. I want to upload pictures through UART # 2. I can currently upload TXT files using UART # 2.

An error is reported when transmitting the picture

hello 540189861,

that error logs shows… err -30.
it is error flag, EROFS, which indicate read-only file system.

is your file system mounted as read-only?

hello JerryChang.Thank you very much for your help.But now there is a new problem when I send pictures to my NX through UART # 2 and ZMODEM again, as shown in the picture.

Hello, JerryChang.What can I do to ensure that I can safely transfer image files to my NX through UART # 2?

What permissions do you see from:
ls -l /dev/ttyTCU0

FYI, an ext4 write error is unlikely related to the file transferring over a UART, although it is possible that the method of transferring from UART to filesystem (software) could cause issues. There are many ext4 inode errors.

Before you go further, how much space is left? What do you see from “df -H -T”? If something has corrupted the filesystem, then this would explain the read-only setting since an unrecoverable filesystem will refuse to mount for write (this avoids further corruption).

Assuming it is read-only due to corruption, then there is no method to transfer anything to that drive without repairing it. Repair is not guaranteed to succeed. Should repair succeed, then it is important to know how the previous transfer attempts were done in case this is the cause of the problem (cutting power without proper shutdown would be another way of causing this, although that degree of corruption probably requires significant writing activity at the time of cutting power).

Is this an SD card model? If it is, then it is simple to try to repair on a host PC.

Hello, linuxdev.Thank you for your help.My NX is an EMMC version.
I can now transfer TXT files below 190KB in size. However, when I try to transfer a 200KB TXT file, an error occurs when I transfer it to about 95%.
When I transfer pictures, I can’t transfer them directly.I use the Xshell serial port tool to connect. The upload mode is ZMODEM.

ZMODEM is unlikely the problem (it is possible that it is trying to send some old dialout modem control sequence, and there is no modem; so that would be “garbage” data if there is a modem init sequence, but it is unlikely this would be the “whole story” even if it is involved. Do make sure it does not send any modem init string.

Where did you get ZMODEM? I’m curious because I don’t see it in the apt repository list for Ubuntu 18.04 (though I’ve used ZMODEM in the past, long ago). Similarly, you mentioned Xshell, and I am curious where that is downloaded?

Before you do anything though we still need to know the output of “ls -l /dev/ttyTCU0”. This is to determine if there is a serial console program interfering. If this is running group “tty” instead of “dialout”, then there is basically no possibility of this working.

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.