From mboxrd@z Thu Jan 1 00:00:00 1970 From: tim@cygnetinc.com (Tim Michals) To: "Lewin A.R.W. Edwards" , Subject: RE: [ECOS] USB host mode support? Date: Tue, 20 Feb 2001 06:17:00 -0000 Message-id: References: <4.3.2.7.2.20010220084532.00b46140@larwe.com> X-SW-Source: 2001-02/msg00331.html Lewin, >I'm curious to know what kind of USB peripherals you think will be >important to support in embedded systems. It would be pretty easy to add >generic HID support, but almost every other device you can think of is >proprietary. There are some generic chipsets e.g. for ATA interfaces and >scanners, but often the implementation is customized so a vanilla driver >won't work properly. Basically you're buying into the whole minefield of >maintaining a general-purpose operating system, when consumers call you and >say "My new widget no worky when I plug it in". So at that point it makes >perfect sense (to me to cross over to a GP OS like Linux, as Bart said. Mostly wireless USB devices, the idea is still to keep the OS very small and able to do some type of plugNPlay. ie download a new OS if required. Dynamic loading would be nice. I agree to some of the ideas of Linux, but the issue is we have a size issue. Yes, USB is a pain to support on the host side. But as devices become more internet and device aware this will become a requirement. Also, it is still me understanding most of the USB device support under Linux must be compiled, therefore, as you add a new device you must recompile the OS? >As another BTW, although eCos doesn't explicitly support dynamic loading, >it is possible to implement it with some magic. I have a (grossly >imperfect) module-loader as a work-in-progress. The reason I need one is >because we wish to allow developers to write add-on modules for our product >without wiping the whole OS out of flash. I seem to recall someone (Grant >Edwards?) writing about a similar need on the list some weeks ago. Thanks -----Original Message----- From: ecos-discuss-owner@sources.redhat.com [ mailto:ecos-discuss-owner@sources.redhat.com]On Behalf Of Lewin A.R.W. Edwards Sent: Tuesday, February 20, 2001 7:53 AM To: ecos-discuss@sources.redhat.com Subject: RE: [ECOS] USB host mode support? Hi Tim, >I think as more embedded systems grow there will be a need for host mode >USB. At this time I'm going to try a do a host mode version. Do you see >any big issues in porting BSD or Linux implementation to eCOS? I'm curious to know what kind of USB peripherals you think will be important to support in embedded systems. It would be pretty easy to add generic HID support, but almost every other device you can think of is proprietary. There are some generic chipsets e.g. for ATA interfaces and scanners, but often the implementation is customized so a vanilla driver won't work properly. Basically you're buying into the whole minefield of maintaining a general-purpose operating system, when consumers call you and say "My new widget no worky when I plug it in". So at that point it makes perfect sense (to me to cross over to a GP OS like Linux, as Bart said. As another BTW, although eCos doesn't explicitly support dynamic loading, it is possible to implement it with some magic. I have a (grossly imperfect) module-loader as a work-in-progress. The reason I need one is because we wish to allow developers to write add-on modules for our product without wiping the whole OS out of flash. I seem to recall someone (Grant Edwards?) writing about a similar need on the list some weeks ago. === Lewin A.R.W. Edwards (Embedded Engineer) Work: http://www.digi-frame.com/ Personal: http://www.zws.com/ and http://www.larwe.com/ "Und setzet ihr nicht das Leben ein, Nie wird euch das Leben gewonnen sein."