I never did it, but if you manage to do it please share with me how, i have one LTE5300 that would benefit from it 😀

To get things talking at all, I had to set the port speed on the Linux server manually to 38400, and modify the source of ATduck to operate at 38400 (as opposed to the default rate of 115200). Things seem to be communicating alright, and terminal on my Windows 3.1 machine produces the desired result on the Linux server.

So I tried it with Trumpet Winsock 1.0 which didn't seem to work, so I found Trumpet Winsock 3.0 which supports PPP (1.0 only supports SLIP). Things seem to be communicating, and SLIRP and Trumpet seem to be handshaking PPP, but.... no love from ping tools (let alone web browsers) in Windows 3.1.

I'll have to spend some time really troubleshooting this... maybe I'll try dial-up from Arachne or something like that to see if it produces a more desireable result.

Maybe any luck with Windows 95 ?

Okay, I got it working just by running agetty on the linux server on the serial port, and doing a manual login from Trumpet... essentially bypassing ATduck and running slirp directly from the command line via serial port, how slirp is intended to be run. I got it working with both SLIP and PPP protocols, and I was able to download files from the web using Netscape at a whopping 3.5K/s (pretty much the limit of a 38400 serial connection)... man, I remember when I got a 14.4k modem which was an upgrade from the 2400baud modem I had before and thought that 14.4k was blazing.

Anyway, I realized that part of my testing that the connection was working was actually flawed... I was trying to ping things after Trumpet "connected" with slirp, but come to find out that slirp is not ICMP friendly, only TCP friendly (basically, it is doing very rudimentary NAT), so my ping tests weren't working... but HTTP request via Netscape works fine 😊 Which means that before when I had Trumpet apparently properly negotiating PPP, it probably was actually working. I'll have to go back and try with ATduck now.

So, I can't seem to get ATduck to work... this might take more coding/effort than I was prepared to. It seems to work, but PPP won't negotiate. It seems like once slirp is enabled after the appropriate phone number is "called" by Trumpet (ATDT5555) that the data is getting mangled somehow... Trumpet quickly gets in an inconsistent errored state. Same is true for Arachne in DOS.

Interestingly though, Trumpet seems to like to simply try and start PPP communication as soon as its started without necessarily running a dial script, so I tried just running slirp directly on the serial port, and it works! Basically, just start slirp:

1slirp "tty /dev/ttyS0"

And start Trumpet (after starting slirp), and its quite happy to do so. No need to run agetty and do a manual login.

I'm sure this is only true with Trumpet... Arachne did not like this arrangement very much (it insists on dialing something first), but it works for my needs... I can browse basic web sites and send/receive files via HTTP (haven't tried FTP yet, but supposedly SLiRP is FTP friendly) in Windows 3.1. Also, I was able to increase the serial speed to 115200 as opposed to the 38400 I was using. It seems that was a limitation of Trumpet Winsock 1.0 that is not a limitation of 3.0 that I have now.

Well thank you for providing information about it, i will try when i get some time, if i can make something i can provide information aswell 😀