Data loss over ttyACM* when 'cat' command is used for data transfer

Question

I have a development board which will have 3 ACM interfaces when connected to Ubuntu host and i want to transfer data from Host to Device over ttyACM3.

I have followed the following procedure for data transfer,

Precondition:

Modify /etc/inittab to remove Linux console on /dev/ttyGS3
Create a binary file with a minimum length of about 20MBytes

Test Steps:

DUT side: stty -F /dev/ttyGS3 raw -echo -echoe -echok -echoctl -echoke
HOST side: stty -F /dev/ttyACM3 raw -echo -echoe -echok -echoctl -echoke
DUT side: cat /dev/ttyGS3 > /tmp/rx_pattern.bin
HOST side: cat ./pattern.bin > /dev/ttyACM3

By following above procedure i see some data(~300 KB) is missed at the DUT side randomly. I have also used "dd" command for data transfer but still there is a data loss.

But i tried to transfer the same "pattern.bin" file from the Host by using "minicom" application and "cat" command to receive from DUT side, surprisingly i don't see any data loss.

I have took USB Ellisys logs during issue scenario,

One of the "OUT" transaction is failed(handshake is NAK) and there is no "PING" transaction for the failed transfer.
Whereas in success scenario whenever "OUT" transaction fails, "PING" transaction is present and data is sent again.

stty command difference on the both the hosts.

Ubuntu 14.04:

speed 115200 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^A; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q;
stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; flush = ^O; min = 1; time = 0;
-parenb -parodd cs8 hupcl -cstopb cread -clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon -ixoff -iuclc -ixany -imaxbel -iutf8
-opost -olcuc -ocrnl -onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
-isig -icanon -iexten -echo -echoe -echok -echonl -noflsh -xcase -tostop -echoprt -echoctl -echoke

Ubuntu 16.04:

speed 9600 baud; rows 0; columns 0; line = 0;
intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q;
stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; discard = ^O; min = 1; time = 0;
-parenb -parodd -cmspar cs8 hupcl -cstopb cread clocal -crtscts
-ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr -icrnl -ixon -ixoff -iuclc -ixany -imaxbel -iutf8
-opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0
-isig -icanon iexten -echo -echoe -echok -echonl -noflsh -xcase -tostop -echoprt -echoctl -echoke -flusho -extproc

Surprisingly if i keep open ACM3 port from Minicom application and tries to send data, there is no data loss even in Ubuntu 14.4.

Some serial ports have limited fifo sizes so if the OS takes too long to read the data you get overruns. Do `sudo cat /proc/tty/driver/serial` and look for `oe:` for built-in serial ports. Are you just testing the devices or do you intend to do real data transfers over this line? — meuh, Jul 16 '18 at 12:29
@Ralph `ixon` command is not working for me. I see Host could send only few bytes when flow control is enabled. — Shivaprasad A Prabhu, Jul 17 '18 at 09:26
@meuh I dont see any entries `oe:`. I need to send the real data(binary) over ttyACM3 for some purpose. — Shivaprasad A Prabhu, Jul 17 '18 at 09:28
If you want reliable data transfer over a serial line you should consider using something like [slip](https://en.wikipedia.org/wiki/Serial_Line_Internet_Protocol) which allows you to treat the connection like an ethernet. It is easy to setup and does not impose much traffic overhead. — meuh, Jul 17 '18 at 11:36
See my [answer](https://unix.stackexchange.com/a/322258/119298), or read [this](https://en.wikibooks.org/wiki/Linux_Networking/SLIP_client). — meuh, Jul 19 '18 at 10:07
@meuh: Anyhow i need to use "cat" command itself for data transfer. **I see there is no data loss when same procedure followed on Ubuntu 16.04**. data loss is present on Ubuntu 14.04 and 18.04. — Shivaprasad A Prabhu, Jul 20 '18 at 13:29
Does `stty -a -F /dev/ttyACM3` show exactly the same parameters when run on Ubuntu 16.04 and on Ubuntu 18.04 ? — Mark Plotnick, Jul 20 '18 at 15:33
@MarkPlotnick: Also `stty` version is different on both the hosts. **Ubuntu 14.04:** `8.21` **Ubuntu 16.04:** `8.25` — Shivaprasad A Prabhu, Jul 23 '18 at 07:36
@MarkPlotnick: Even though i configured `stty` of 14.04 is same as 16.04, there is a data loss. — Shivaprasad A Prabhu, Jul 23 '18 at 13:03

Data loss over ttyACM* when 'cat' command is used for data transfer

Precondition:

Test Steps:

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