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Messages - Eric

31
General discussion / Re: Data-sheet interchange
I guess I don't understand what we would be trying to do.  There are at least dozens if not hundreds of whole sites devoted to just collecting and linking data sheets -- just search Google for "data sheet" and you'll find plenty.  What would we be trying to do that is different than them?

(Opps -- I had thought I had found one of the data sheets someone was looking for but it was a slightly different part).  If you have done an exhaustive search of all the data sheet sites, a Google search, and looked through all the surplus chip supplier web sites and still can't find it then I don't think we will be able to do any better.  I've never looked but there are probably even news groups and mailing list dedicated to this sort of thing.  I may be missing the point but I don't see what the small group of people we have here can do any better than what is already out there.

-Eric
32
Web platform / Re: FreeRTOS
I had a little time last night to start working with this.  All I have really done so far was get the code from SVN, get the project configured in MPLAB 8, get it to compile and program the PIC.  I did then test that the serial console is spitting out log messages and the uIP stack is acquiring a DHCP assigned IP address but that was as far as I got. 

I think I should have some time this weekend to work on it.  Matt, I'll leave the web server part to you.  I think I will look at trying to get the telnet server working and tied in with the serial console if I can.  If there is anything else you would like me to take a look at let me know.

-Eric
34
USB Infrared Toy / Re: IR Toy with web platform
[quote author="geegos"]
Somehow I believe that it's even more complicated to hook them together via serial link than adding an IR to the web platform. [/quote]

I don't know that linking the two via a logic level serial link would be any harder than adding the LED driver to the Web Platform but, having two processors to just send some IR commands would be a bit overkill.

[quote author="geegos"]
Does anyone have a good tutorial or datasheet which shows how to wire up a LED to web platform (or sth. comparable) and additionaly a good tutorial to firmware programming? [/quote]

I would start with the wiki page for the Web Platform.  It has lots of info, the data sheet, and links to other useful information including an introduction to dsPIC33 programming.  Lots of additional info about PIC programming is available via a web search.

 -Eric
35
USB Infrared Toy / Re: IR Toy with web platform
[quote author="geegos"]
Well I guess it would be too difficult for me to "reinvent" the ir toy. [/quote]

It certainly could be done.  I have not looked at the code for the IR Toy or the current Web Platform so I have no idea how hard it would be.

[quote author="geegos"]
But the FreeRTOS aspect would be nice. But the project isn't that far right now, is it?[/quote]

No, it is not very far along.  There has only been one person working on it so far.  I just got the hardware and so hope to start helping out soon.

[quote author="geegos"]
But afterall I'm quiet a newbie at microcontrollers ;) Just made really basic things in VDHL at the university. But someone can always learn ;)
[/quote]

These are actually good projects to learn on because they are small enough and simple enough to get involved with.  Personally, I find microcontroller programming (in C or assembly) easier than VHDL.  But that is just my opinion and my VHDL experience is old and limited.

-Eric
36
Web platform / Re: FreeRTOS
I just got my Web Platform this week.  Now, as soon as I can find some time, I will start helping with the FreeRTOS implementation.  Has there been any recent progress?

-Eric
37
USB Infrared Toy / Re: IR Toy with web platform
If we are able to get FreeRTOS running on the Web Platform then it should be much easier to do things like this.  Adding this functionality would be accomplished by running the relevant IR Toy code in a new thread.  This is the kind of thing FreeRTOS makes much easier.  If you already have most of work done as stand alone code then adding it to a FreeRTOS project is usually not too hard and much easier than trying to add the functionality to typical embedded supper loop code.

-Eric
39
Bus Pirate Support / Re: Bus Pirate came in handy again...
Ian, it must have been a slow day for news if that post of mine made the front page.

[quote author="Rubu"]
Ha! a Linksys router? A roommate of mine had a similar issue with his router, and I remember thinking how handy the BP would come in there. Eventually we solved it by shorting some GPIO pins to ground for a specific number of seconds, but that took quite a few tries to get right.
[/quote]

No, not a Linksys, though it is replacing an old faithful WRT54G (4MB early model).  The new router is a Buffalo WZR-HP-G300NH.  It is probably one of the best deals going out there right now that supports OpenWRT.  It has a 400MHz MIPS processor with 64MB RAM and 32MB flash, five gigabit Ethernet ports, wireless 802.11b/g/n, and a USB host port for attached storage all for $69.99 at newegg.com (limit five per customer) <--- I guess newegg thinks they really are that great of a deal.

I have it configured somewhat backwards to how you would normally think of using the Ethernet ports.  I have it set for dual WAN connections coming in two of the numbered ports that you would normally use for the LAN.  These will be load balanced, one on DSL and the other on a cable modem.  All reports from people that live in the neighborhood I am moving to say both are slow and somewhat unreliable so I am planning to split the risk with one of each.  The router has three NAT'ed subnets for the LAN.  These all come out as tagged VLANs on the port marked on the back for the internet(WAN).  This is then connected to an Ethernet switch that supports both tagged and untagged (port based) VLAN configuration.  One subnet/VLAN will be for me, one for my roommate, and then one for guests, etc.  Each subnet also has a separate wifi network interface (three different SSIDs) as well.  I hope to eventually do a captured portal on the guest subnet/VLAN.  It is kind of hard to explain without getting down in to details most people won't care about.

If you can imagine, you have to be kind of careful as you make all these changes because you are swapping the Ethernet devices that the router treats as the LAN and the WAN.  Because you are changing where the LAN attaches to the router it is not hard to get the router in a state where you have no LAN connection to the router's ssh or web interfaces.  I successfully managed to get it all configured without locking myself out by moving the Ethernet ports while connected via wireless and then moving the wifi while connected via an Ethernet port.  Then clear at the end I was cleaning up some of the configuration files and forgot to make some changes in one of the files before I rebooted.  Now I was locked out.  I did not want to lose everything by resetting to factory defaults and starting all over.  So, the only other way to fix it was with the serial console -- which thankfully they at least bring out to an unpopulated header.  And this is where the Bus Pirate came in to the story.

-Eric
40
Bus Pirate Support / Bus Pirate came in handy again...
I am trying to get a new router setup for when I move to a more permanent home here in a couple weeks.  At some point I messed up a config file or two and locked myself out of all the lan subnets/VLANS.  I had to pop open the case to get at the serial console.  This is brought out to a row of unpopulated .100" holes and operates at 3.3v levels.  I of course had my Bus Pirate laying on my desk/workbench.  In a matter of seconds I had the console up in a terminal window using the transparent pass through macro.  A couple quick vi edits and the Ethernet connections were back up. 

This of course isn't anything terribly special.  I have several USB to serial converters in my parts bin that I could have used for this.  But the versatility of the Bus Pirate means it is always getting used and so always right at hand for the next job.

Another very satisfied customer.


-Eric
41
General discussion / Re: Multimeter purchase question
That sounds like a good price as long as it is in decent shape. 
Since it's via Craigslist I assume you will be able to actually handle it before you pay.

I would do a quick function check.  Make sure the volt readings go to zero when you short the leads.  If there is an AC outlet handy check to see if that reading makes sense.  If you have a small battery in your pocket check that too.  Make sure the continuity and ohms meter are working open and shorted. 

Most meters I have seen either work fine or have obvious problems.  Also do a test on the two internal fuses (it's in the manual) and drop your offering price if either is blown.  They are easy to replace but it is a good bargaining point.

You can find all the manuals on Fluke's site if you haven't already found them.

-Eric
42
General discussion / Re: Multimeter purchase question
I don't know where they are manufacturing what these days but I have not had any bad experiences with their meters.  The 70 series is probably the minimum I would recommend.  The 80 series has a great reputation as well but I would probably recommend going with a 189/289 series if you want to get more than a 79.  I definitely recommend looking on eBay.  You have to be careful and take your time but if you can wait you can get a great deal.  I bought a 189 in nearly brand new condition a number of years ago off eBay.  I do not remember the specifics anymore but I want to say I paid somewhere between 25-35% of new cost.

-Eric
43
Open Bench Logic Sniffer / Re: Alternative Java client
[quote author="ian"]
Is it feasible to add a live preview or scrolling live capture mode...[/quote]

While not as sophisticated as a scrolling live capture, most of the logic analyzers I have used have had a sort of live preview called Activity Indicators.  These are more akin to a logic probe on each channel (Hi,Low,Pulse) but provide a good idea of what is happening and may be easier to implement.

-Eric
44
Web platform / Re: Linux Development
Outstanding!  This is the best news I have seen from Microchip in a long time and I've been using their stuff for a long time (well at least since when the PIC16C84 was brand new and MPLAB was a 16bit Windows application, 3.x I think).

Curiously though it seems like they are not yet supporting Linux x86-64 but only x86-32.  Has anyone tried installing the Linux version on an x86-64 Linux platform yet?

-Eric
45
Web platform / Re: FreeRTOS
[quote author="mattcallow"]
The FreeRTOS port is now in svn:  trunk/web-platform/FreeRTOS[/quote]

Good news.  As soon as I get a Web Platform I'll start working with it.

-Eric