On Sat, Oct 11, 2003 at 04:52:28PM -0500, Ron Johnson wrote: > On Sat, 2003-10-11 at 11:51, Pigeon wrote: > > A dead-tree advert I have suggests > > http://www.ObservantWorld.com , who make a thing called a "Data > > Station" that gives you a bunch of analogue and digital inputs and > > outputs and is controlled via RS232. Or you could program a PIC > > microcontroller to do the job. > > > Do you think these RS232 devices could be controlled by a USB-Serial > adapter?
Undoubtedly. The devices made by http://www.ftdichip.com have support in the Linux kernel which appears to emulate the IOCTLs of a standard serial port, and it seems you can drive an ordinary modem with them. http://www.ftdichip.com/FTDriver.htm#LINUX http://ftdi-usb-sio.sourceforge.net/ > (Since on-board serial is slowly going the way of the dinosaur?) ...a situation which I consider to be dead and chewed, as I agree with your Einstein quote from some other thread and reckon that USB is way too complex for anything that doesn't require the high data rate... I build some PIC-microcontroller-based gadget that is controlled by sending it a single character at infrequent intervals; RS232 is ideal, as some PIC microcontrollers have the hardware built in, on those that don't it's trivial to implement it in software, and you can use bell wire for the data cable. USB is way over the top. You can't do it in software on a PIC because they're not fast enough. Even if a PIC with USB hardware was available it'd still need to run rather faster than normal to keep up with the bus. (Fast microcontrollers are scarce and expensive; the requirements are more often for low power consumption and simplicity of interfacing.) The FTDI devices mentioned above do the job, but they are expensive, and are quite likely to cost more than all the other electronic parts put together. Similarly, I consider it to be dead and chewed that digital radio broadcasting is being introduced as a replacement for analogue broadcasting, not as an additional service. I predict that we'll end up seeing a generation of hardware engineers whose proficiency suffers because they were introduced to the subject academically in their teens or later, as opposed to being introduced by natural interest by building crystal sets when they were little. -- Pigeon Be kind to pigeons Get my GPG key here: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x21C61F7F
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