Hi, On Wed, Jan 07, 2015 at 11:16:33AM +0700, Jean-Luc Aufranc wrote: > I've also taken some picture of my setup -> > https://picasaweb.google.com/110719562692786994119/UNITUT16E?authuser=0&feat=directlink > I bought the multimeter @ > http://www.dx.com/p/ut61e-2-6-lcd-digital-multimeter-red-black-1-x-9v-6f22-battery-113306 > in October 2014. > lsusb for the USB to serial adapter: http://pastebin.com/KVAtJbg0
Aha, that's likely the problem: idVendor 0x1a86 QinHeng Electronics idProduct 0x7523 HL-340 USB-Serial adapter We've seen other (USBHID-to-serial) adapters from QinHeng that do "strange" things to the data. If you have another USB-to-serial adapter with an FTDI or Prolific chip I'm pretty sure it'll work fine (you already mentioned in another post that using a real RS232 port also works fine). > Output using cutecom (ttyUSB0 / 19200 7O1) with Ohm range set to kOhm and > .0L: > > 00000000: 31 32 32 b5 38 b0 b3 31 b0 b0 b0 b0 0d 8a 31 32 Yep, this looks incorrect and is likely caused by the QinHeng adapter. The "0d 8a" should be "0d 0a" for example, it looks like the adapter messes around with the parity bit and thus breaks the protocol. There are workarounds for this, we're doing a similar thing for the UT-D04 cable that's shipped with some UNI-T devices, e.g. http://sigrok.org/gitweb/?p=libsigrok.git;a=blob;f=src/hardware/uni-t-dmm/protocol.c;h=37144980fa108ea13e5b880274b491e686ec47ff;hb=HEAD#l225 Not sure whether it makes sense to add a workaround for this specific USB-to-serial device (and where) in libsigrok. Where did you get this USB-to-serial device? Was it shipped with the multimeter or bought extra (and it's not intended to be used with this device)? Uwe. -- http://hermann-uwe.de | http://randomprojects.org | http://sigrok.org ------------------------------------------------------------------------------ Dive into the World of Parallel Programming! The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net _______________________________________________ sigrok-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/sigrok-devel
