[PLUG] com port in guest to usb in host (virtual box)

Denis Heidtmann denis.heidtmann at gmail.com
Mon Dec 11 02:11:42 UTC 2017


The protocol I recall seeing documented was 7n2, 600 baud.  I must confess
I do not know how to talk directly over serial.  I tried Google, but there
were too many options and opinions.  What do you recommend for this simple
task?

On Sun, Dec 10, 2017 at 3:01 PM, Russell Senior <russell at personaltelco.net>
wrote:

> Try talking to the DMM directly over serial.  The protocol description
> says:
>
>   Various multimeters from Metex (and rebadged ones) use this common
> 14-byte packet based ASCII protocol. The actual multimeter ICs in the
> devices have different names (e.g. "MASTECH M343-01" or "Metex
> KS57C2016") but they all use the same common protocol format.
>
>   The serial port settings can vary from device to device, e.g.
> 600/1200 baud, 7n2, RTS low, DTR high.
>
> If you get the serial parameters right, you ought to be able to talk
> directly at it (e.g. send a D and get a string of bytes).  Maybe you
> can snoop the serial with an oscilloscope while running the vendor
> interface software and figure out the baud,et al.
>
> On Sun, Dec 10, 2017 at 2:08 PM, Denis Heidtmann
> <denis.heidtmann at gmail.com> wrote:
> > Thanks for the -help.  I got part of that -help when I entered an
> incorrect
> > option, but somehow missed the -- entries at the end.  Here is what I
> get:
> >
> > denis at denis-ThinkPad-L420:~$ sigrok-cli --driver
> > mastech-mas345:conn=/dev/ttyUSB0 --scan
> > The following devices were found:
> > mastech-mas345 - MASTECH MAS345 with 1 channel: P1
> >
> > denis at denis-ThinkPad-L420:~$ sigrok-cli --driver
> > mastech-mas345:conn=/dev/ttyUSB0 --show
> > mastech-mas345 - MASTECH MAS345 with 1 channel: P1
> > Supported driver options:
> >     conn
> >     serialcomm
> > Supported configuration options:
> > denis at denis-ThinkPad-L420:~$
> >
> > Additionally I tried:
> > denis at denis-ThinkPad-L420:~$ sigrok-cli --driver
> > mastech-mas345:conn=/dev/ttyUSB0 --loglevel 5
> > sr: libsigrok loglevel set to 5.
> > sr: backend: Sanity-checking all drivers.
> > sr: backend: Sanity-checking all input modules.
> > sr: backend: Sanity-checking all output modules.
> > srd: libsigrokdecode loglevel set to 5.
> > Usage:
> >   sigrok-cli [OPTION...]
> > snip...
> >
> > I also tried the --output-file but nothing.  I found that I could not
> enter
> > more than one option at a time---I tried --scan and --show but only the
> > first one was responded to.
> >
> > BTW, recall that this instrument worked as expected using the vendor's
> > windows sw on the desktop, where I have a serial port.  So I do not
> suspect
> > the hardware outside the laptop.
> >
> > These results are encouraging, but no cigar.
> >
> > -Denis
> > _______________________________________________
> > PLUG mailing list
> > PLUG at pdxlinux.org
> > http://lists.pdxlinux.org/mailman/listinfo/plug
> _______________________________________________
> PLUG mailing list
> PLUG at pdxlinux.org
> http://lists.pdxlinux.org/mailman/listinfo/plug
>



More information about the PLUG mailing list