Tried it. No response. Not sure how I got back to a functioning terminal, but now: denis@denis-ThinkPad-L420:~$ sigrok-cli --driver mastech-mas345:conn=/dev/ttyUSB0 --scan sr: serial: Error opening port (16): Device or resource busy. denis@denis-ThinkPad-L420:~$
On Sun, Dec 10, 2017 at 11:32 PM, Russell Senior <[email protected]> wrote: > The signaling on a PC RS232 line is +nV and -nV, where n is somewhere > between 5 and 12, inclusive. So, I think -6V would be a zero and a > +6V would be a one. > > I think you can use GNU screen here, with the following options > (serial parameters are from the manpage from stty(1): > > screen /dev/ttyUSB0 600,cs7,cstopb,-parenb > > Not sure this is doing the suggested thing for RTS and DTR. > > On Sun, Dec 10, 2017 at 8:41 PM, Denis Heidtmann > <[email protected]> wrote: > > I notice that 12 V is mentioned. I measure ~6 V from ground to every pin > > except RxD, which is zero. (All DC; when not sending data.) Could this be > > the issue? > > > > On Sun, Dec 10, 2017 at 6:28 PM, Denis Heidtmann < > [email protected]> > > wrote: > > > >> Here is the protocol description I recall finding: > >> > >> MAS345: > >> > >> data format: 7n2 at 600 baud (7 bits, no parity, 2 stop bits). > >> Control lines: > >> DTR and RTS lines are used to power the TX line: RTS is clear > >> for -12 supply; DTR is set for +12 supply. Data transmission is > >> solicited sending whatever character to the RX line. > >> Data string format: > >> MAS-345 sends a 14 bytes string with: > >> <mode>< ><sign><value>< ><units><return> > >> <mode>: two bytes with the oerating mode: DC, AC, OH, CA, TE ... > >> <sign>: one byte with - or space > >> <value>: five bytes with four digits and one decimal dot. > >> <units>: four bytes with the units: mV, A, kOhm, nF ... > >> <return>: '\r' > >> One space is inserted between <mode> and <sign>, one between > >> <value> and <units>. > >> The data string (without the '\r') is sent to the output device. > >> > >> On Sun, Dec 10, 2017 at 6:11 PM, Denis Heidtmann < > >> [email protected]> wrote: > >> > >>> 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 < > >>> [email protected]> 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 > >>>> <[email protected]> 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@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@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@denis-ThinkPad-L420:~$ > >>>> > > >>>> > Additionally I tried: > >>>> > denis@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 > >>>> > [email protected] > >>>> > http://lists.pdxlinux.org/mailman/listinfo/plug > >>>> _______________________________________________ > >>>> PLUG mailing list > >>>> [email protected] > >>>> http://lists.pdxlinux.org/mailman/listinfo/plug > >>>> > >>> > >>> > >> > > _______________________________________________ > > PLUG mailing list > > [email protected] > > http://lists.pdxlinux.org/mailman/listinfo/plug > _______________________________________________ > PLUG mailing list > [email protected] > http://lists.pdxlinux.org/mailman/listinfo/plug > _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
