Not sure if this is possible, or something you would want to implement but I will throw it out to see if it sticks.

I'm working with some "retro" 1980's computers that do not have the
capability of downloading files at the maximum connection speed they can
access the BBS. In these cases, some of these computers can connect at
38.4K, but may only be able to maintain 9600 or 19.2 rates of transfer.

Others, may only be able to sustain file transfer rates of 2400 to 4800 baud.

To accommodate differences between screen displays and file transfer speeds, would it be possible to add an optional command parameter that can be passed from a User Setting so the user can configure their download speed which
would be controlled from the connection from Mystic?

As I said, not sure if it is something you would consider, but I thought I would throw it out there anyways.

Beery

--Beery Miller -- 9640 News BBS -- 9640news.ddns.net:9640 --

--- Mystic BBS v1.12 A38 2018/01/01 (Windows/64)
* Origin: 9640 News BBS (21:4/109)

On 02/07/18, Beery said the following...

I'm working with some "retro" 1980's computers that do not have the capability of downloading files at the maximum connection speed they can access the BBS. In these cases, some of these computers can connect at 38.4K, but may only be able to maintain 9600 or 19.2 rates of transfer.

There is some handshaking even with just a three wire interface (checksums
and ACKs) so the sender should slow to the receivers top speed. With old machines there is more handshake signals that can be used on the serial ports and the USB serial for a Pi would use them. The common way is to use a Pi to interface old serial with telnet over the net and it should work fine even on most of the oldest machines. Are you really having trouble with them?

--- Mystic BBS v1.12 A38 2018/01/01 (Linux/64)
* Origin: Workpoint (21:1/145.3)

There is a project in the works with the PI, however it has not been made available beyond alpha/beta testers at this point using an interface board to the PI. I do not believe the project has a serial interface. This project involves using the PI as a file server host to files local on the SD card as well as other site hosted files.

If you are aware of something from computer serial to PI to Telnet, please
let me know.

What these older computers are using now are not PI emulations of these computers, rather real hardware. They are interfacing with Telnet using the Lantronix UDS-10, the WiModem232, or a WiFi modem.

If there was a way/setting that could be passed to the download protocol to throttle down the download speed without the user logging in at a lower
speed, that would be a way to solve some file transfer speed issues.

Beery

--Beery Miller -- 9640 News BBS -- 9640news.ddns.net:9640 --

--- Mystic BBS v1.12 A38 2018/01/01 (Windows/64)
* Origin: 9640 News BBS (21:4/109)

On 02/12/18, Beery said the following...

What these older computers are using now are not PI emulations of these computers, rather real hardware. They are interfacing with Telnet using the Lantronix UDS-10, the WiModem232, or a WiFi modem.

If there was a way/setting that could be passed to the download protocol to throttle down the download speed without the user logging in at a
lower speed, that would be a way to solve some file transfer speed
issues.

Take a look at http://www.insentricity.com/a.cl/215/putting-your-retro-computer-on-the-line

tcpser is being used to emulate a modem and take URL instead of phone numbers: sudo apt-get install tcpser
tcpser -s <maxspeed> -d /dev/ttyUSB0
ATDTbbs.fozztexx.com:6502

If 19200 is the max rate of the PC then use that for maxspeed. It will buffer the incoming data. It makes a Pi with a USB serial interface and null modem cable work as a virtual modem to the old PC and get it on the net via telnet.

--- Mystic BBS v1.12 A38 2018/01/01 (Raspberry Pi/32)
* Origin: Mystic Pi BBS bcw142.zapto.org (21:1/145)

Thanks for that link. I've got a PI, and if I have the appropriate cables, I will see how the PI responds.

Beery

--Beery Miller -- 9640 News BBS -- 9640news.ddns.net:9640 --

--- Mystic BBS v1.12 A38 2018/01/01 (Windows/64)
* Origin: 9640 News BBS (21:4/109)