From fb56292e278db07345cea9bc48a23886574b5189 Mon Sep 17 00:00:00 2001 From: "W. Trevor King" Date: Wed, 19 Jun 2013 09:16:21 -0400 Subject: [PATCH] posts:open-hardware-analog-io: Add post on open analog I/O Also update the open source force spectroscopy post to link to my thesis. --- posts/Open_hardware_analog_IO.mdwn | 53 +++++++++++++++++++++++ posts/Open_source_force_spectroscopy.mdwn | 3 +- 2 files changed, 55 insertions(+), 1 deletion(-) create mode 100644 posts/Open_hardware_analog_IO.mdwn diff --git a/posts/Open_hardware_analog_IO.mdwn b/posts/Open_hardware_analog_IO.mdwn new file mode 100644 index 0000000..3e19a42 --- /dev/null +++ b/posts/Open_hardware_analog_IO.mdwn @@ -0,0 +1,53 @@ +[[!meta title="Open hardware analog I/O"]] + +Over at [Software Carpentry][SWC], Greg Wilson just posted [some +thoughts about a hypothetical open science framework][GW]. He uses +Ruby on Rails and similar web frameworks as examples where frameworks +can leverage standards and conventions to take care of most of the +boring boilerplate that has to happen for serving a website. Greg +points out that it would be useful to have a similar open science +framework that small projects could use to get off the ground and +collaborate more easily. + +My [[thesis|Thesis]] is about developing an [[open source framework +for single molecule force +spectroscopy|Open_source_force_spectroscopy]], so this is an avenue +I'm very excited about. However, it's difficult to get this working +for experimental labs with a diversity of the underlying hardware. If +different labs have different hardware, it's hard to write a generic +software stack that works for everybody (at least at the lower levels +of the stack). Our lab does analog control and aquisition via an old +National Instruments card. NI no longer sells this card, and +developing [[Comedi]] drivers for new cards is too much work for many +to take on pro bono. This means that new labs that want to use my +software can't get started with off the shelf components; they'll need +to find a second-hand card or rework the lower layers of my stack to +work with a DAQ card that they can source. + +I'd be happy to see an inexpensive, microprocessor-based open hardware +project for synchronized, multi-channel, near-MHz analog I/O to serve +as a standard interface between software and the real world, but +that's not the sort of thing I can whip out over a free weekend +(although I have [[dipped my toe in the water|AVR]]). I think the +missing component is a client-side version of [libusb][], to allow +folks to write the firmware for the microprocessor without dealing +with the intricacies of the [USB specs][USB]. It would also be nice +to have a standard USB protocol for Comedi commands, so a single +driver could interface with commodity DAQ hardware—much like the +current situation for [mice, keyboards, webcams, and other approved +classes][USB-class]. Then the software stack could work unchanged on +any hardware, once the firmware supporting the hardware had been +ported to a new microprocessor. There are two existing classes (a +[physical interface device class][PID] and a [test and measurement +class][TM]), but I haven't had time to dig through those with an eye +toward Comedi integration yet. So much to do, so little time… + +[[!tag tags/hardware]] + +[SWC]: http://software-carpentry.org/blog/2013/06/twelve-bar-blues-of-science.html +[GW]: http://software-carpentry.org/blog/2013/06/twelve-bar-blues-of-science.html +[libusb]: http://www.libusb.org/ +[USB]: http://www.usb.org/developers/docs/ +[USB-class]: http://www.usb.org/developers/devclass_docs#approved +[PID]: http://www.usb.org/developers/devclass_docs/pid1_01.pdf +[TM]: http://www.usb.org/developers/devclass_docs/USBTMC_1_006a.zip diff --git a/posts/Open_source_force_spectroscopy.mdwn b/posts/Open_source_force_spectroscopy.mdwn index 0bc5c04..5f9fa96 100644 --- a/posts/Open_source_force_spectroscopy.mdwn +++ b/posts/Open_source_force_spectroscopy.mdwn @@ -1,6 +1,7 @@ There are a number of open source packages dealing with aspects of [[single-molecule force spectroscopy|force_spectroscopy]]. Here's a -list of everything I've heard about to date. +list of everything I've heard about to date (for more details on +calibcant, Hooke, and sawsim, see my [[thesis|Thesis]]). -- 2.26.2