TODO

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Revision as of 22:07, 5 May 2011 by Uwe Hermann (talk | contribs) (Add some TODOs.)
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sigrok 0.3

  • Get rid of the use of manual polling of FDs, which is not portable (doesn't work on Windows). Use g_poll() instead (which spawns a new thread on Windows).
  • Mac OS X: B460800 is not available it seems. Find the correct header (if any) and/or find a (possibly platform-specific) workaround, or drop this on Mac OS X.
  • Add a --start-sampling (TODO: Better name?) option, which just starts sampling with the supplied or default samplerate. Contrary to --time or --samples you don't need to explicitly specify a duration or number of samples here, that's automatically determined by the available memory of the logic analyzer and the selected samplerate.
    • TODO: Similar to --continuous? Merge both?
  • Make sure all combinations of --enable-*/--disable-* options works for configure.
    • There may be issue if none of the drivers is enabled, print useful error in that case(?)
  • libsigrok.h/libsigrokdecode.h: Only list public API functions.
  • Windows port:
    • Implement anykey.c replacement.
    • hex output: Not all lines/columns are of the same length (as they are with real LAs).
    • VCD: All samplenumbers are 0 (instead of the proper samplecount).
    • OLS, gnuplot: Hangs on MinGW for some reasons (not sure if related).
  • Finish protocol decoder API design.
  • CLI/libsigrok: Eliminate all printing to stdout, only sample data or decoder output should end up there. Error/debug messages should go to stderr always.
    • Also, libsigrok should never print anything directly via (f)printf or similar, only via sr_info()/sr_err()/sr_dbg().
  • MinGW: Fix Python path decoder issues due to Windows vs. Linux path specification.
  • Run the code receiving the samples as quickly as possible, run output format code and other non-timing-critical stuff (protocol decoders) in an extra thread. The problem is nicely visible with FX2-based logic analyzers, the longer and output format takes to produce it's output, the better your chances to get "oops, I just lost samples" errors.
  • Hardware drivers: Make specification of triggering capabilities more detailed, so that frontends/GUIs can auto-generate GUI forms out of that metadata.

sigrok 0.4

  • stackable protocol decoder implementation
  • modular filter system
    • take arguments in the regular thing:key=value format
    • integrate current probe compression filter
    • resampling module: sample up/down based on factor argument
    • noise filter: filter out pulses shorter than the samplerate's period

Before 1.0

  • all output modules should use GString API instead of estimating output size
  • VCD input modules
  • OLS format input module

Future

  • udev:
    • Make udev optional, only build MSO driver if it's available
    • have OLS driver use udev if available, fall back to serial port probing otherwise
    • Find alternative to udev for windows and macos
  • Fix/workaround libusb 1.0 Windows port issues:
    • Device renumeration not yet supported (needed for FX2 based LAs)
    • File descriptor / socket based polling not supported in Windows. Workaround (short-term): Use a thread in sigrok.
  • Make sure all optional components are really optional in the build system:
    • Only require Python if the users wants protocol decoders, the rest should also build/compile/run fine without Python installed.
  • sigrok uses uint64_t as an internal datatype to represent a sample, limiting the number of probes on supported hardware to 64. But high-end logic analyzers can have hundreds of probes. A solution would be to switch to either a roll-our-own byte array type, or use GMP. In any case, the overhead of switching over shouldn't be too bad: the filter code and frontend datafeed callback functions will need to use it, but hardware drivers should have enough with a couple of lightweight wrappers.
  • sr_errno:
    • Most functions should return SR_OK or SR_ERR_* (same for SRD_OK etc).
    • Most backend functions return status as an integer, which is SR_OK if all went well, or SR_ERR_* and similar if an error occurred.
    • However there is no way to pass any information back as to what went wrong — and this is important for user-friendliness.
    • Perhaps an error code is not enough; maybe something like sigrok_errno(errorcode, "unsupported device") is better.
  • Clean up device-specific globals in hardware drivers, to properly permit multiple devices per driver: asix-sigma, demo (not relevant), link-mso19, openbench-logic-sniffer, saleae-logic, zeroplus-logic-cube
  • Python bindings for libsigrok and libsigrokdecode.

Contributors wanted

  • Add output for latex package tikz-timing.
  • Linux distro packages for non-Debian distros.
  • FreeBSD packages/ports.
  • Open-source firmware for the FX2 devices

The Cypress FX2-based devices, such as the Saleae Logic and the USBee SX, use only a minimal vendor-provided firmware. The only thing it really does is set the sample rate and turn on the chip's auto-mode. Nevertheless, the vendors provide the firmware as a binary blob, with no source. It would be great if sigrok could ship with an own firmware implementation for these devices. Some links:

    • SDCC, the Small Devices C Compiler, is a compiler specifically suited to small MCUs, and has support for the 8051 core in the FX2.
    • fx2lib is an open-source library for writing firmware on the FX2. It has a number of interesting functions, including implementing custom USB vendor commands.
    • GNU Radio's USRP2 board has an FX2 on it, and GNU Radio has extensive custom firmware for it.