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Netduino Plus Firmware v4.2.0 RC1


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#21 Edward

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Posted 21 August 2011 - 06:10 PM

No. We're awaiting a revised build from Secret Labs. See http://netmf.codeple...m/workitem/1166

#22 ajcg1973

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Posted 29 August 2011 - 05:20 AM

Chris, Has anything changed with how USBClient works in 4.2? More specifically is it possible to boot directly into USBClient being connected instead of waiting for the device to be ready to connect?---AJB

#23 Chris Walker

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Posted 29 August 2011 - 06:05 AM

Has anything changed with how USBClient works in 4.2? More specifically is it possible to boot directly into USBClient being connected instead of waiting for the device to be ready to connect?---AJB

No changes to USBClient in .NET MF 4.2.

Chirs

#24 Earthed

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Posted 31 August 2011 - 01:23 AM

Essential reading: http://forums.netdui...k-v42-sdk-beta/

#25 liqdfire

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Posted 05 September 2011 - 12:37 PM

Setup: 4.2 RC1 firmware
4.2 RC2 SDK (could not find the download for RC1)

I am getting an exception trying to use RegEx:

#region Constructors
public DataHolder()
{
  _regex = new Regex("(?<result>.*)(\\r\\n)+(?<response>OK|ERROR|>){1}");
}
#endregion


An unhandled exception of type 'System.Text.RegularExpressions.RegexpSyntaxException' occurred in System.Text.RegularExpressions.dll

Additional information: Syntax error: Missing operand to closure

The regex works just fine on desktop, and Derek Slager's regex tester.

#26 Edward

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Posted 05 September 2011 - 01:11 PM

I bumped into this too. The regex library is a port of an old (but worthy) Apache Java library (Jakarta)to C# (it's not native). It doesn't support quite the same syntax as the desktop .Net regex library (which is a little irritating). One thing that's not implemented is named capture groups af far as I'm aware. There are also some differences on what characters have to be escaped. I ended up downloading the library source and compiling it to find this out. Maybe these inconsistencies are worthy of a 'bug' on CodePlex. For me the performance from a non-native library and its cosiderable memory footprint made me look for simpler techniques for what I was trying to achieve.

#27 liqdfire

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Posted 05 September 2011 - 01:54 PM

I bumped into this too.
The regex library is a port of an old (but worthy) Apache Java library (Jakarta)to C# (it's not native).
It doesn't support quite the same syntax as the desktop .Net regex library (which is a little irritating). One thing that's not implemented is named capture groups af far as I'm aware. There are also some differences on what characters have to be escaped.

I ended up downloading the library source and compiling it to find this out.

Maybe these inconsistencies are worthy of a 'bug' on CodePlex.

For me the performance from a non-native library and its cosiderable memory footprint made me look for simpler techniques for what I was trying to achieve.


It looks like not having the support for named capture groups causes a difference in the way the regex compiler recognizes the syntax.
I changed my regex to "(.*)(\\r\\n)+(OK|ERROR|>){1}" and it had no problem with that.

#28 magarcan

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Posted 04 October 2011 - 11:22 AM

How many free ROM is this firmware going to leave for us??? Actually we only have 64KB.

#29 liqdfire

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Posted 06 October 2011 - 11:00 PM

How many free ROM is this firmware going to leave for us??? Actually we only have 64KB.


Not much, I actually ended up taking regex out because the referenced assemblies were 30k just but themselves

#30 magarcan

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Posted 10 October 2011 - 07:24 AM

Not much, I actually ended up taking regex out because the referenced assemblies were 30k just but themselves

I think this is the big problem with Netduino. If you test the sample codes, for example all code in Getting Started with the Internet of Things, but when you begin making some bigger you will realise that you can't flash your firmware because it is bigger than the amount flash available.

#31 liqdfire

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Posted 10 October 2011 - 03:34 PM

I think this is the big problem with Netduino. If you test the sample codes, for example all code in Getting Started with the Internet of Things, but when you begin making some bigger you will realise that you can't flash your firmware because it is bigger than the amount flash available.


Well I think you just hit on the crux of embedded development; it has to be kept at the forefront of though that these devices are resource limited, they are not anywhere near as powerful as desktops so part of the project development process is making the attempt to keep the code base as small as possible. Which unfortunately means doing things differently than you would normally do if it was a desktop application you were writing.

I had originally started using regex in my netMF project because it makes life really easy, but the trade off for ease of code dev on my end for the amount of resources it took up was not worth it, so I had to go back to doing manual string evaluation and manipulation.

#32 Stefan

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Posted 10 October 2011 - 04:16 PM

Well I think you just hit on the crux of embedded development

I have to agree here, although it can also be a bottleneck, you have to work (around) some limitations. I always consider that a challenge!
"Fact that I'm a moderator doesn't make me an expert in things." Stefan, the eternal newb!
My .NETMF projects: .NETMF Toolbox / Gadgeteer Light / Some PCB designs

#33 magarcan

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Posted 10 October 2011 - 04:47 PM

I've been developing with Atmel uC for some years, and I had never found this problem. I can tell you that I've developed some big projects, but always using C. My favourite micro use to be AtMega32.

#34 liqdfire

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Posted 10 October 2011 - 05:17 PM

I've been developing with Atmel uC for some years, and I had never found this problem. I can tell you that I've developed some big projects, but always using C. My favourite micro use to be AtMega32.


That very well may be, but are you keeping in mind that there is a trade off between convenience and code size. There is absolutely nothing stopping anyone from writing native applications in uC and running them on the Netduino.




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