User:PeterMortensen

Recent activity

2017-12

Recording 22483 traces for the purpose of evaluating a proposed fix to the CAN protocol decoder (actually only changing a single number from 16 to 17), stuff bit at the very end of the CRC segment, with a modified trigger scheme: change the position of the trigger point at the end so there is always a CAN message in the trace (for the previous), but still 26 µs recessive. The time division was 100 µs / division (about 225 bit times max) to always record whole CAN messages - at 10 samples per bit time.

2017-07

Using the sigrok command-line ("sigrok-cli") to bulk process data derived from Tektronix oscilloscope data of 250 kbit/s CAN traffic on a real-world system (mobile cranes). The first sample data set is 5335 oscilloscope traces obtained with the trigger set to a negative pulse on CAN-H (to start off at the end of a CAN message) - corresponding to 6.5 recessive bits, 26 µsec (detecting the space in-between CAN messages). Sometimes there is a CAN message right after this, sometimes it is a bit delayed, and sometimes it is completely empty.

A sample command line (on Windows) is:

sigrok-cli -P can:bitrate=250000:can_rx="CAN RX" -P timing:data="CAN RX" -I csv:header=true:samplerate=5000000 -i "T:\stdHMF\UserData\scripts\Tektronix2PulseView\_PulseView_AllChannels_ACQ000001_Tektronix_f5000000.txt"

2017-04

Using PulseView to decode data from a Tektronix oscilloscope of SPI communication to a CAN controller, MCP2515.

Task list

Currently not in priority order.

• Allow import of analog data through CSV files. (Related: fixed bug 1064 - locale issue, decimal point, "," vs. ".".).

• Add detection of error frames to the CAN protocol decoder

• Add support for the gigga watt EEVBlog multimeter (Bluetooth, etc.)

• Add a snap feature to the "cursor" (blue) in PulveView

• Change number of significant digits for the time display in the "cursor" (blue) in PulveView

• Submit selected sample traces for CAN decoder change (for CRC segment) validation. With and without stuff bits in various places. With and without timing deviations. (Related: bug 1085, celeron55's fix, if len(self.bits) > self.last_databit + 16 → if len(self.bits) > self.last_databit + 17 (16 → 17)).

• Add support for the TDS2000 series in libsigrok, and thus, by extension, use by the new shiny stuff in PulveView.

On wiki

• Change recommended procedure for submitting sample Sigrok files (traces), on Example dumps.

Interests

I am mostly interested in:

• The CAN protocol decoder (that page is currently empty, but it is listed on the protocol decoders page)
• CAN bus loggers, like IXXAT's (now acquired by HMS) USB-to-CAN compact/USB-to-CAN V2 and Kvaser's Memorator.
• The higher-level CANopen protocol (on top of CAN)

Protocol decoders

Non-empty wiki pages

Currently (2017-07-08), 28 of 77 protocol decoders (36%) have non-empty pages here on the wiki:

• ADNS5020
• AM230X
• ARM ETMV3
• ARM ITM
• ARM TPIU
• AUD
• AVR PDI
• DCF77
• I²C
• IR NEC
• Modbus
• MRF24J40
• NRF24L01
• Nunchuk
• PAN1321
• Parallel
• PWM
• Qi
• RFM12
• RGB LED SPI
• RTC8564
• SPDIF
• SPI
• SPI flash
• Stepper motor
• TLC5620
• UART
• Z80

Profile

Profile: see my Wikipedia user page.

Credentials: more than 5000 edits on the English Wikipedia.

Shortcuts

• sigrok-cli man page
• Google+ group for sigrok
• PulseView. Includes the command line to get the source code using Git.
• PulseView, Windows binaries (nightly - development). Alternative location (but it seems redundant).
• Example data dumps - sample data in .sr format. Also includes instructions on how to contribute new ones. Includes the command line to get the whole thing using Git (as of 2017-11-26, 2286 "objects", 724 .sr files, about 65 MB in download size, 192 MB on disk).
• Random page
• Native app image (not official yet). Is for Linux and x86 only. See also AppImage (Wikipedia).

Protocol decoders

• The CAN bus protocol decoder
• Protocol decoder HOWTO
• Protocol decoder API
• Supported protocol decoders

Building sigrok

• On Debian (e.g. Raspberry Pi): Installing required software
• On Debian (e.g. Raspberry Pi): Actual build
• Alternative to following the wiki pages: a script that will do most of it. ([sigrok-util.git] / cross-compile / linux / sigrok-cross-linux)