I'd do prep and all the heavy lifting with a PC that has a real serial
terminal, get it working correctly, and then tackle the USB2Serial issues.
Not all adapters work correctly and they are a headache to rely on.
b

On Wed, Jul 15, 2026 at 12:23 PM Brent Hilpert via cctalk <
[email protected]> wrote:

> On 2026Jul 15,, at 8:26 AM, Jon Elson via cctalk <[email protected]>
> wrote:
> >
> > I am trying to get my old VMS system going for demo at VCFMW.
> >
> > I got a USB-serial adapter, and it mostly works OK.  I am using minicom,
> and trying to get the Emulex firmware resident diagnostics loaded on the
> uVAX.  This requires entering a BUNCH of ODT commands.  I tried to put
> these in a file, and then do an ASCII send file command in minicom, but it
> gets garbled.  I assumed that minicom was sending too fast, so put in a
> bunch of delays on each character and on linefeed.  I did this in the T
> (terminal) menu.  I can clearly see these delays work when typing on the
> keyboard, but they DON'T seem to work when sending the file, as the file
> send doesn't take any longer to complete.  Is there another place to set
> delays that is effective for ASCII send?
> >
> > Also, minicom doesn't seem to save these terminal (T) settings when
> restarted.
> >
> > Should I be using a different program?
>
>
> This sounds like the inherent problem with USB-serial adapters.
>
> The terminal program (minicom in your case) may well be adding the
> per-character delay, but somewhere in the host-to-USB stream the characters
> are accumulated in a buffer/packet, when the USB adapter finally gets them
> it sends them out to its serial port all at the regular bps rate, sans the
> inter-character delay.
>
> Or at least, I have had such a flow control problem in trying to emulate a
> paper-tape reader  (for downloading BASIC programs to an HP2116). Adding
> delays, adding TC_FLUSHES to the terminal program, etc., were of no effect.
> In that  situation, I was eventually able to resolve it by adding some code
> to (my) terminal program to wait for the LF returned by the receiving
> software (BASIC interpreter on the 2116) after sending the EOL CR, that is,
> using the LF as an ACK.
>
> If it might work for your situation, or if you want a hackable terminal
> program:
>         http://madrona.ca/e/scomm/index.html
>
>

Reply via email to