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Pushing the limits....backwards

By GuruOfDos ·
MS and the hardware makers keep adding new features, new enhancements and even more bloatware, but at the same time, they are also removing things, and not always telling us.

Computers have two, and ONLY two, root functions. Processing information (be it matehmatical, text, graphical or whatever) according to defined parameters (input, program and output). That's one. The other.....CONTROL!!!

And where is the control??

1980s....CBM Pet, Vic20, etc had a 22-way connector on the back called, oddly enough, a USER PORT...hook up your electronic circuits, PEEK and POKE a few bytes and hey presto...CONTROL!!! Robot arms, central heating, alarm systems, whatever!!

1990's.... The IBM PC has IO mapped addresses for hardware sat on the ISA bus...&H300=&H3FF was defined as a 'Prototyping Area' and you could build hardware and talk to it with INP and OUT in GWBasic, or IN and OUT in assembler. I design and build ISA cards that do all kinds of 'magic'.

2000' more ISA, and OS's that DON'T allow direct reads and writes to hardware registers or addresses. I'm still having to use 9x because this WILL let me talk to the hardware directly but now my new PC doesn't have ISA slots so where does that leave me?? Hooked up to the LPT port because that still has 5 TTL Inputs and 8 TTL outputs. Need more?? Add another PCI printer port card!!!

Now everyone has Firewire, USB2.0, and suchlike and the powers that be say that the LPT port (and COM ports) are about to become extinct. So where do we go from here? Stay with 'obsolete' technology or move over to dedicated process control electronics which then takes away the computer front end? Are we only going to end up with half a computer...all process and no control? All right, it's a faster, better machine but has progress taken away one of the two fundamentals of computing...the ability to communicate with the 'real world'?

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by jcmcmahon In reply to Pushing the limits....bac ...

Look at B&B Electronics at

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Thanks...but not a real-time solution!

by GuruOfDos In reply to

Thanks for the site info....but that method still involves serial (yawn!) communication and not only that but conversion between serial formats (RS232-RS485 etc....). Yes it 'does' mean 'expandable', but it is about the slowest method of reading fast moving data in real time.

For example, we use three ultrasonic pressure-wave sensors connected to a computer IO card. A pressure wave from a weapon being fired inside a firing range will generate a logic pulse on each of the (suitably positioned) sensors, and the time differences between the pulses give positional and timing information (e.g. to indicate the order and times at which firers in the lanes shot at their targets...for assessing reaction times etc). The logic signals can be monitored in real-time using a direct IO mapped card, but there is no way we can do this using serial interfaces without a LOT of extra hardware. One of our engineers DID build an interface with a Xilinx CoolRunner PLD and wrote some software in VHDL to send RS232 information to and from a PC, but our original method cost about ?5 (US$7.50) for a cheap PCB and a few LS TTL IC's and did the job in real-time, and his method cost into the thousands and took several seconds to interrogate the interface and receive data back!

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to much tech

by warbug In reply to Thanks...but not a real-t ...

All you need is a stopwatch and a good eye guru, use your tech toys to keep your coffee warm while your working....ahhhh for the glory days of vacuum tubes and punch cards....:]

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