Galen, thanks for the Clinic offer, but I will not be able to make it there.
Since my last report I have set the baud rate and bits: denis@denis-ThinkPad-L420:~$ stty -F/dev/ttyUSB0 -a speed 600 baud; rows 0; columns 0; line = 0; intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = <undef>; eol2 = <undef>; swtch = <undef>; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; werase = ^W; lnext = ^V; discard = ^O; min = 1; time = 0; -parenb -parodd -cmspar cs7 hupcl -cstopb cread clocal -crtscts -ignbrk -brkint -ignpar -parmrk -inpck -istrip -inlcr -igncr icrnl ixon -ixoff -iuclc -ixany -imaxbel -iutf8 opost -olcuc -ocrnl onlcr -onocr -onlret -ofill -ofdel nl0 cr0 tab0 bs0 vt0 ff0 isig icanon iexten echo echoe echok -echonl -noflsh -xcase -tostop -echoprt echoctl echoke -flusho -extproc What I do not seem to be able to set is "no parity". I see odd and even but not none in man stty. The protocol is supposed to be: data format: 7n2 at 600 baud (7 bits, no parity, 2 stop bits). The narrowest pulse is 1.6ms except for a 0.8ms pulse at the start. The wide pulse is 5ms with a space of 3.3ms. On Fri, Dec 15, 2017 at 11:36 AM, Galen Seitz <[email protected]> wrote: > On 12/14/17 21:24, Denis Heidtmann wrote: > > Measuring with a 'scope with the laptop issuing the command sigrok-cli > > --driver mastech-mas345:conn=/dev/ttyUSB0 --samples 10: > > > > triggering on DTR > > > > DTR goes from -6.6V to +7.6V and remains there 'till 9.64s > > RX goes from -2.6V to +6.4V for .48s then again at 2.6s,3.12s, etc 'till > > 7.32s (10 groups of data pulses after the initial .48s wide group) > > RTS sits at -6.4V except for a narrow spike to +6.6V at 2.44s > > TX starts at -6.4V 'till 2.6s, 3.12s, etc where it has a double pulse of > > 5ms each spaced 1.7ms. These pulse groups start synchronously with the RX > > groups. > > > > If I want to get more detail I think I need to trigger on TX. > > > > So it looks like data is being sent. Is it received and sent to a bit > > bucket, or not received by the usb-to-serial device? How to find out? > > I think you should first confirm the baud rate. Put your scope on the > RX line (assuming that's the output from the DMM) and look for the > narrowest positive or negative pulse. That pulse width should tell you > what baud rate the DMM is using. Confirm that you have configured the > serial port correctly. > > Do you have a digital scope? If not, I can see how you might have > trouble capturing these single shot events. I could probably make it to > the clinic on Sunday if you'd like some help with this. > > galen > -- > Galen Seitz > [email protected] > _______________________________________________ > PLUG mailing list > [email protected] > http://lists.pdxlinux.org/mailman/listinfo/plug > _______________________________________________ PLUG mailing list [email protected] http://lists.pdxlinux.org/mailman/listinfo/plug
