The filtering API that’s built into the stream (i.e. TCP) side of the licensed framework is pretty powerful. It’s what the OpenSSL, SChannel and SSPI Negotiate filters use to transform the data as it flows into and out of your server without you needing to do anything special; it’s what the flow control filter uses to provide efficient TCP window based flow control; it’s what the compression filter uses to compress your data stream; it’s what the read timeout filter uses to provide you with asynchronous read timeouts on overlapped I/O and what the connection re-establishment filter uses to automatically reconnect if your connection goes down.

Previously published This article was previously published on lhexapod.com as part of my journey of discovery into robotics and embedded assembly programming. A full index of these articles can be found here. Whilst playing around with my servo controller I realised that the power used by a servo goes up considerably when it’s under heavy load (such as when it’s pressing against the table and still trying to move). I can, potentially, get an idea of this load by measuring the current that each servo is using and using this feedback somehow.

Previously published This article was previously published on lhexapod.com as part of my journey of discovery into robotics and embedded assembly programming. A full index of these articles can be found here. I decided to treat myself to an early christmas present and bought a 60W temperature controlled soldering station (a ZD-916 which I got from Maplin). All I can say is WOW. Suddenly I can solder neatly rather than making a smeary mess.

Previously published This article was previously published on lhexapod.com as part of my journey of discovery into robotics and embedded assembly programming. A full index of these articles can be found here. This is the AVR Studio project and assembly language source code files for the latest version (v7.0) of my 64 channel serial servo controller. This is the latest version of the ATMega168 version of the code which includes all of the new servo commands that I wrote about here including the multi-move command and the unit tests that I spoke of here.

Previously published This article was previously published on lhexapod.com as part of my journey of discovery into robotics and embedded assembly programming. A full index of these articles can be found here. The latest version of the serial servo controller is now fully operational (I’ll upload the source code shortly). There are still some bugs that I’m finding but the work I put in to getting the unit tests in place makes fixing these bugs pretty straight forward.

I’ve been spending a little time recently writing a custom Wireshark dissector plugin for the UDT protocol. This didn’t prove to be that difficult once I got over the initial problem of actually getting the Wireshark source to build with VS2008. My problem was that I’d found a CodeProject article which is now slightly out of date and which I followed too closely - setting up the Platform SDK version that the article stated was required.

As I mentioned a while back the CLR Hosting API has changed with .Net 4.0. The new API allows you much more flexibility in loading CLR runtimes and also allows you to load and run multiple different runtimes in a single process. Whilst this is useful if you need to control which runtime runs your code and indispensable if you need to host code that really requires different versions of the runtime and can’t all run in the “latest” runtime, I think the times when a user of my CLRHosting libraries will actually need this functionality will be few and far between.

The licensed version of my freely available I/O Completion Port based, high performance, Windows networking framework provides a whole host of features that the free code doesn’t; aside from performance improvements, bug fixes and an active support and development process. These features make writing highly scalable TCP and UDP clients and servers very easy and solve many of the problems that you would come across if you were to start from scratch, either with the Winsock API directly or using something such as boost::asio.

Compressing TCP (and reliable UDP) streams is one of the things that often comes up in discussion with clients and I’ve helped several people implement stream compression using the TCP stream filtering API that’s part of The Server Framework. The filtering API is also used to provide SSL security over a stream and for things like asynchronous read timeouts, read sequencing, flow control and automatic reconnects. It’s a flexible API and the fact that it’s pluggable means that you can pick and choose from the various filters that form part of the framework and add whichever combination you fancy.

Previously published This article was previously published on lhexapod.com as part of my journey of discovery into robotics and embedded assembly programming. A full index of these articles can be found here. It’s taken me almost a month but I’m finally back to working on integrating the multiple servo move command into the rest of the code. Well, the integration was done long ago, unfortunately the debugging was the bit that was taking up my time.