I'm turning to you people as I am at a loss with regards to the following issue:

On #rc2014bbs I use KMD to provide #xmodem transfer over the serial line (and, eventually via #wifimodem over the internet).

This works as long as you either connect with another #rc2014 using #qterm or #imp or if you use a #Commodore64 using #ccgms

But when you try to perform xmodem transfer from a modern machine (PC, Mac - it doesn't matter) using a modern terminal program (Syncterm, Qodem, TeraTerm, lrzsz etc. - it doesn't matter) the transfer begins, sending a few blocks and then gets into a NAK loop and aborts due to the error count reaching max.

So, my question to the wise, collective fedimind is: what can be the cause for such a behaviour? Timing issues?! Old xmodem implementation within KMD?! Some interference from the #Zimodem firmware?!

Any suggestions, comments etc. are welcome!

+++ Sysop News +++ Sysop News +++

So I'm still investigating the connectivity issues I witnessed with #rc2014bbs and here are my current findings:

1.) while the telnet listener of the #Zimodem firmware is no longer open on port 2014, the #wifi of the #esp8266 itself is still active and the reserved ip is responding to ping requests.

2.) once the firmware gets reset via ATZ it sometimes restarts /re-opens the listener on port 2014

3.) the listener dies a few hours after initial powerup of the system

4.) my memory may be failing me but those issues began somewhere around autumn last year when I updated the firmware to version 3.7.1

As a result of these findings, I have reverted the firmware on the esp8266 to Zimodem version 3.6.5. It's not an official release - I checked it out using the corresponding commit hash.

The BBS was powered up with that version yesterday at 09:00 am and it is still running about 24 hours later, which was never the case with the 3.7.1 version of the firmware. I've also noticed a few other glitches not being present with the 3.6.5 version.

It is still a little too soon to call the problem solved, but there's movement here.

Also keep in mind that RC-BOX BBS (the world's first and - currently - only #rc2014 based #bbs) is using a wifi connection so other sources of influence may also have an effect on connectivity (although they never were *that* worse before 3.7.1).