If you mustuse. NET System. IO. Ports. Serial. Port Hardware, Software Product Development. As an embedded developer who writes desktop software mostly for configuration of, and data download from, peripheral devices, I use serial data streams a lot. Mostly USB virtual serial posts from FTDI, but also the USB Communication Device Class and real 1. UARTs on the PCI bus. Since looking at data through an in circuit emulator debug interface is generally    a miserable experience, getting serial data communication with a custom PC application is essential to analyzing data quality and providing feedback on hardware designs. C and the. NET Framework provide a rapid application development that is ideal for early development that needs to track changing requirements as hardware designs evolve. Ideal in most respects, I should say. The System. IO. Ports. Serial. Port class which ships with. NET is a glaring exception. To put it mildly, it was designed by computer scientists operating far outside their area of core competence. They neither understood the characteristics of serial communication, nor common use cases, and it shows. Nor could it have been tested in any real world scenario prior to shipping, without finding flaws that litter both the documented interface and the undocumented behavior and make reliable communication using System. IO. Ports. Serial. Port henceforth IOPSP a real nightmare. Plenty of evidence on Stack. Overflow attests to this, from devices that work in Hyperterminal but not. NET because IOPSP makes setting certain parameters mandatory, although they arent applicable to virtual ports, and closes the port on failure. Theres no way to bypass or ignore failure of these settings during IOPSP initialization. Whats even more astonishing is that this level of failure occurred when the underlying kernel. APIs are immensely better Ive used the Win. API before working with. NET, and still do when I want to use a function that. Kilauea Mount Etna Mount Yasur Mount Nyiragongo and Nyamuragira Piton de la Fournaise Erta Ale. NET doesnt have a wrapper for, which notably includes device enumeration. The. NET engineers not only failed to devise a reasonable interface, they chose to disregard the Win. Serial Port Delphi 7 Components Of Pain' title='Serial Port Delphi 7 Components Of Pain' />API design which was very mature, nor did they learn from two decades of kernel team experience with serial ports. A future series of posts will present the design and implementation of a rational serial port interface built upon, and preserving the style of, the Win. API serial port functions. It fits seamlessly into the. NET event dispatch model, and multiple coworkers have expressed that its exactly how they want a serial port class to work. But I realize that external circumstances sometimes prohibit using a CCLI mixed mode assembly. The CCLI solution is incompatible with Partial trust not really a factor, since IOPSPs Open method also demands Unmanaged. Code permissionSingle executable deployment there may be workarounds involving ILMerge or using netmodules to link the C code into the CCLI assemblyDevelopment policies that prohibit third party projects. NET Compact Framework no support for mixed mode assembliesThe public license as yet undetermined might also present a problem for some users. Or maybe you are responsible for improving IOPSP code that is already written, and the project decision maker isnt ready to switch horses. This is not a good decision, the headaches IOPSP will cause in future maintenance far outweigh the effort of switching, and youll end up switching in the end to get around the unfixable bugs. So, if you fall into one of these categories and using the Base Class Library is mandatory, you dont have to suffer the worst of the nightmare. There are some parts of IOPSP that are a lot less broken that the others, but that youll never find in MSDN samples. Unsurprisingly, these correspond to where the. NET wrapper is thinnest. That isnt to say that all the bugs can be worked around, but if youre lucky enough to have hardware that doesnt trigger them, you can get IOPSP to work reliably in limited ways that cover most usage. I planned to start with some guidance on how to recognize broken IOPSP code that needs to be reworked, and thought of giving you a list of members that should not be used, ever. But that list would be several pages long, so instead Ill list just the most egregious ones and also the ones that are safe. The worst offending System. IO. Ports. Serial. Port members, ones that not only should not be used but are signs of a deep code smell and the need to rearchitect all IOPSP usage The Data. Received event 1. The Bytes. To. Read property completely unreliableThe Read, Read. Existing, Read. Line methods handle errors completely wrong, and are synchronousThe Pin. Changed event delivered out of order with respect to every interesting thing you might want to know about itMembers that are safe to use The mode properties Baud. Rate, Data. Bits, Parity, Stop. Bits, but only before opening the port. And only for standard baud rates. Hardware handshaking control the Handshake property. Port selection constructors, Port. Name property, Open method, Is. Open property, Get. Port. Names method. And the one member that no one uses because MSDN gives no example, but is absolutely essential to your sanity The only serial port read approaches that work correctly are accessed via Base. Stream.   Its implementation, the System. IO. Ports. Serial. Stream class which has internal visibility you can only use it via Stream virtual methods is also home to the few lines of code which I wouldnt choose to rewrite. Finally, some code. Heres the wrong way the examples show to receive data. Data. Received portData. CkV8/U1-RtdZNOaI/AAAAAAAAAl0/rSfrpqLJezg/s1600/adf02802d40e14546137681ddea02bf6.png' alt='Serial Port Delphi 7 Components Of Pain' title='Serial Port Delphi 7 Components Of Pain' />Received. Data. Received event. Bytes. To. Read. Readbuffer, 0, buffer. YYuzC.png' alt='Serial Port Delphi 7 Components Of Pain' title='Serial Port Delphi 7 Components Of Pain' />Update 8517 725pm ET Googles new Vice President of Diversity, Integrity Governance Danielle Brown has issued her own memo to Google employees in response to. Connecting external electonics using the parallel port. For hobbyists and educators. Length. raise. App. Serial. Data. Eventbuffer. IOException exc. App. Serial. Errorexc. Data. ReceivedportData. Received later, in Data. Received event    bytebuffernewbyteport. Bytes. To. Read    port. Readbuffer,0,buffer. Length    raise. App. Serial. Data. Eventbuffer    handle. App. Serial. Errorexc Heres the right approach, which matches the way the underlying Win. API is intended to be used. Limit. Action kickoff. Read null. kickoff. Read delegate. Base. Stream. Begin. Readbuffer, 0, buffer. Length, delegate IAsync. Result ar. int actual. Length port. Base. Stream. End. Readar. Length. Buffer. Block. Copybuffer, 0, received, 0, actual. Length. raise. App. Serial Port Delphi 7 Components Of Pain' title='Serial Port Delphi 7 Components Of Pain' />Search Independent Sales Opportunities. We network independent sales reps seeking new product lines with nationwide manufacturers from all industries offering 100. Accreditation. West Virginia University Institute of Technology is accredited by The Higher Learning Commission as a division of West Virginia University. No one wants to buy a used car only to have expensive problems pop up down the road. This is especially true if youre dropping some serious money on a sports or. Serial. Data. Eventreceived. IOException exc. App. Serial. Errorexc. Read. kickoff. Read bytebuffernewbyteblock. Limit    port. Base. Stream. Begin. Readbuffer,0,buffer. Tennis Game Pc Ware'>Tennis Game Pc Ware. Length,delegateIAsync. Result ar            intactual. Lengthport. Base. Stream. End. Readar            bytereceivednewbyteactual. Length            Buffer. Block. Copybuffer,0,received,0,actual. Length            raise. App. Serial. Data. Eventreceived            handle. App. Serial. Errorexc It looks like a little bit more, and more complex code, but it results in far fewer pinvoke calls, and doesnt suffer from the unreliability of the Bytes. Trek Valencia Plus Manual. To. Read property. Yes, the Bytes. To. Read version can be adjusted to handle partial reads and bytes that arrive between inspecting Bytes. To. Read and calling Read, but those are only the most obvious problems. Starting in. NET 4. Read. Async on the Base. Stream object, which calls Begin. Read and End. Read internally.