Notably in this case, "VOLT:AC +5.000000E+00,+1.000000E-04" and *E. $ sigrok-cli --driver=agilent-dmm:conn=/dev/ttyUSB0 -O analog --continuous -l 5 sr: [00:00.000002] log: libsigrok loglevel set to 5. sr: [00:00.000077] backend: libsigrok 0.6.0-git-b2e9b6d4/4:0:0 (rt: 0.6.0-git-b2e9b6d4/4:0:0). sr: [00:00.000144] backend: Libs: glib 2.50.3 (rt: 2.50.3/5003:3), libzip 1.1.2, libserialport 0.1.1/1:0:1 (rt: 0.1.1/1:0:1), libusb-1.0 1.0.21.11156, libftdi 1.3. sr: [00:00.000186] backend: Host: i686-pc-linux-gnu, little-endian. sr: [00:00.000225] backend: SCPI backends: TCP, RPC, serial, USBTMC. sr: [00:00.000274] backend: Sanity-checking all drivers. sr: [00:00.000315] backend: Sanity-checking all input modules. sr: [00:00.000352] backend: Sanity-checking all output modules. sr: [00:00.000390] backend: Sanity-checking all transform modules. srd: libsigrokdecode loglevel set to 5. sr: [00:00.004444] hwdriver: sr_config_list(): key 2147418112 (NULL) sdi (nil) cg NULL -> [uint32 20000, 20001] sr: [00:00.004501] serial: Opening serial port '/dev/ttyUSB0' (flags 1). sr: [00:00.023085] serial: Parsing parameters from "9600/8n1". sr: [00:00.023198] serial: Setting serial parameters on port /dev/ttyUSB0. sr: [00:00.027087] serial: Flushing serial port /dev/ttyUSB0. sr: [00:00.027137] serial: Wrote 7/7 bytes. sr: [00:00.158138] serial: Received 44: 'Agilent Technologies,U1252A,SG52430104,V0.91'. sr: [00:00.158224] serial: Closing serial port /dev/ttyUSB0. sr: [00:00.162107] hwdriver: Scan found 1 devices (agilent-dmm). sr: [00:00.162156] device: agilent-dmm: Opening device instance. sr: [00:00.162164] serial: Opening serial port '/dev/ttyUSB0' (flags 1). sr: [00:00.181120] serial: Parsing parameters from "9600/8n1". sr: [00:00.181223] serial: Setting serial parameters on port /dev/ttyUSB0. sr: [00:00.185242] session: Using thread-default main context. sr: [00:00.185279] session: Starting. sr: [00:00.185294] hwdriver: agilent-dmm: Starting acquisition. sr: [00:00.185313] std: agilent-dmm: Sending SR_DF_HEADER packet. sr: [00:00.185339] session: Running transform module 'nop'. sr: [00:00.185354] transform/nop: Received packet of type 10000, passing on unmodified. sr: [00:00.185373] session: bus: Received SR_DF_HEADER packet. cli: Received SR_DF_HEADER. sr: [00:00.185516] hwdriver: sr_config_get(): key 30000 (samplerate) sdi 0xb8e6aa98 cg NULL -> uint64 5 Press any key to stop acquisition. sr: [00:00.195798] agilent-dmm: Sending 'CONF?'. sr: [00:00.195862] serial: Wrote 8/8 bytes. sr: [00:00.215139] serial: Read 1/1 bytes. sr: [00:00.217150] serial: Read 1/1 bytes. sr: [00:00.218138] serial: Read 1/1 bytes. sr: [00:00.221901] serial: Read 1/1 bytes. sr: [00:00.221939] serial: Read 1/1 bytes. sr: [00:00.222098] serial: Read 1/1 bytes. sr: [00:00.224120] serial: Read 1/1 bytes. sr: [00:00.225142] serial: Read 1/1 bytes. sr: [00:00.226134] serial: Read 1/1 bytes. sr: [00:00.266096] serial: Read 1/1 bytes. sr: [00:00.267070] serial: Read 1/1 bytes. sr: [00:00.275120] serial: Read 1/1 bytes. sr: [00:00.276143] serial: Read 1/1 bytes. sr: [00:00.277146] serial: Read 1/1 bytes. sr: [00:00.278143] serial: Read 1/1 bytes. sr: [00:00.280143] serial: Read 1/1 bytes. sr: [00:00.281138] serial: Read 1/1 bytes. sr: [00:00.282139] serial: Read 1/1 bytes. sr: [00:00.284140] serial: Read 1/1 bytes. sr: [00:00.285139] serial: Read 1/1 bytes. sr: [00:00.286139] serial: Read 1/1 bytes. sr: [00:00.288128] serial: Read 1/1 bytes. sr: [00:00.289123] serial: Read 1/1 bytes. sr: [00:00.290123] serial: Read 1/1 bytes. sr: [00:00.291123] serial: Read 1/1 bytes. sr: [00:00.293145] serial: Read 1/1 bytes. sr: [00:00.294105] serial: Read 1/1 bytes. sr: [00:00.295106] serial: Read 1/1 bytes. sr: [00:00.297136] serial: Read 1/1 bytes. sr: [00:00.298151] serial: Read 1/1 bytes. sr: [00:00.299098] serial: Read 1/1 bytes. sr: [00:00.301143] serial: Read 1/1 bytes. sr: [00:00.302142] serial: Read 1/1 bytes. sr: [00:00.303144] serial: Read 1/1 bytes. sr: [00:00.304105] serial: Read 1/1 bytes. sr: [00:00.306144] serial: Read 1/1 bytes. sr: [00:00.307145] serial: Read 1/1 bytes. sr: [00:00.308142] serial: Read 1/1 bytes. sr: [00:00.310142] serial: Read 1/1 bytes. sr: [00:00.310156] agilent-dmm: Received '"VOLT:AC +5.000000E+00,+1.000000E-04"'. sr: [00:00.310248] agilent-dmm: Unknown line '"VOLT:AC +5.000000E+00,+1.000000E-04"'. sr: [00:00.512508] agilent-dmm: Sending 'STAT?'. sr: [00:00.512565] serial: Wrote 8/8 bytes. sr: [00:00.542098] serial: Read 1/1 bytes. sr: [00:00.544112] serial: Read 1/1 bytes. sr: [00:00.545103] serial: Read 1/1 bytes. sr: [00:00.547145] serial: Read 1/1 bytes. sr: [00:00.548141] serial: Read 1/1 bytes. sr: [00:00.549143] serial: Read 1/1 bytes. sr: [00:00.550140] serial: Read 1/1 bytes. sr: [00:00.552141] serial: Read 1/1 bytes. sr: [00:00.553140] serial: Read 1/1 bytes. sr: [00:00.554177] serial: Read 1/1 bytes. sr: [00:00.556179] serial: Read 1/1 bytes. sr: [00:00.557170] serial: Read 1/1 bytes. sr: [00:00.558171] serial: Read 1/1 bytes. sr: [00:00.560171] serial: Read 1/1 bytes. sr: [00:00.561170] serial: Read 1/1 bytes. sr: [00:00.562170] serial: Read 1/1 bytes. sr: [00:00.563173] serial: Read 1/1 bytes. sr: [00:00.565170] serial: Read 1/1 bytes. sr: [00:00.566170] serial: Read 1/1 bytes. sr: [00:00.567172] serial: Read 1/1 bytes. sr: [00:00.569170] serial: Read 1/1 bytes. sr: [00:00.570170] serial: Read 1/1 bytes. sr: [00:00.571135] serial: Read 1/1 bytes. sr: [00:00.573134] serial: Read 1/1 bytes. sr: [00:00.574133] serial: Read 1/1 bytes. sr: [00:00.574191] agilent-dmm: Received '"000001I00210L00004101"'. sr: [00:00.574280] agilent-dmm: STAT response '000001I00210L00004101'. sr: [00:00.574327] agilent-dmm: Sending 'FETC?'. sr: [00:00.574384] serial: Wrote 8/8 bytes. sr: [00:00.593145] serial: Read 1/1 bytes. sr: [00:00.595138] serial: Read 1/1 bytes. sr: [00:00.596138] serial: Read 1/1 bytes. sr: [00:00.597139] serial: Read 1/1 bytes. sr: [00:00.599139] serial: Read 1/1 bytes. sr: [00:00.600139] serial: Read 1/1 bytes. sr: [00:00.601139] serial: Read 1/1 bytes. sr: [00:00.603139] serial: Read 1/1 bytes. sr: [00:00.604125] serial: Read 1/1 bytes. sr: [00:00.605139] serial: Read 1/1 bytes. sr: [00:00.606139] serial: Read 1/1 bytes. sr: [00:00.608139] serial: Read 1/1 bytes. sr: [00:00.609290] serial: Read 1/1 bytes. sr: [00:00.610087] serial: Read 1/1 bytes. sr: [00:00.612088] serial: Read 1/1 bytes. sr: [00:00.613119] serial: Read 1/1 bytes. sr: [00:00.614135] serial: Read 1/1 bytes. sr: [00:00.614204] agilent-dmm: Received '+1.26000000E-02'. sr: [00:00.614320] agilent-dmm: FETC reply '+1.26000000E-02'. sr: [00:00.614373] agilent-dmm: Sending 'FETC? @2'. sr: [00:00.614441] serial: Wrote 11/11 bytes. sr: [00:00.671140] serial: Read 1/1 bytes. sr: [00:00.673170] serial: Read 1/1 bytes. sr: [00:00.675173] serial: Read 1/1 bytes. sr: [00:00.676170] serial: Read 1/1 bytes. sr: [00:00.676206] agilent-dmm: Received '*E'. sr: [00:00.676384] agilent-dmm: Unknown line '*E'. sr: [00:00.878172] agilent-dmm: Sending 'FETC? @2'. sr: [00:00.878193] serial: Wrote 11/11 bytes. sr: [00:00.934180] serial: Read 1/1 bytes. sr: [00:00.935172] serial: Read 1/1 bytes. sr: [00:00.937176] serial: Read 1/1 bytes. sr: [00:00.938141] serial: Read 1/1 bytes. sr: [00:00.938169] agilent-dmm: Received '*E'. sr: [00:00.938361] agilent-dmm: Unknown line '*E'. sr: [00:01.006884] session: Stopping. sr: [00:01.006925] hwdriver: agilent-dmm: Stopping acquisition. sr: [00:01.006947] session: fd_source_finalize: key 0xb8e60e30 sr: [00:01.006980] device: agilent-dmm: Closing device instance. sr: [00:01.006997] serial: Closing serial port /dev/ttyUSB0. sr: [00:01.011139] std: agilent-dmm: Sending SR_DF_END packet. sr: [00:01.011176] session: Running transform module 'nop'. sr: [00:01.011192] transform/nop: Received packet of type 10001, passing on unmodified. sr: [00:01.011210] session: bus: Received SR_DF_END packet. cli: Received SR_DF_END. g_variant_unref: assertion 'value->ref_count > 0' failed