Hi, It depends on the rate of change and response that you need. You mentioned real time, so I assume you need something close to analog control gear in terms of response time. In a closed system (that is, you know how big it will get, it won't get any more inputs/outputs in its lifetime), you can calculate what sort of response time you will get if you have one monitor for several inputs, assuming all inputs are changing. In a variable system, where you are adding or removing i/o, you may be better served with a 1:1 relationship between input and monitor. This becomes more critical in the case of safety control systems, but is less of an issue if it is just the garden lights.
For control and feedback mechanisms you might want to brush up on some control theory and maths if you want to avoid oscillatory systems. Sorry I can't advise you on free tools; my control systems were in microcontroller assembler or C (many microcontrollers come with A/D and D/A converters), but I think you could get away with 'dd' from the command line if your device has a driver... Cheers, Jill. -----Original Message----- From: Richard Hayes [mailto:[EMAIL PROTECTED] Sent: Wednesday, 20 July 2005 6:31 AM To: [email protected] Subject: [SLUG] [OT] What tools for an automatic control system Dear list, I am thinking about creating an automatic control system. The main purpose is to maintain an established relationship between say, temperature and pressure. E.g. If the temperature is too high, reduce pressure There will be a number of real time data feeds. 1. Would it be better if each data feed / sensor had it own independent 'agent' / servlet to monitor its function or is a single integrated system to monitor all the sensors? 2. What free tools exist to monitor systems? Any other suggestions. ---------- Richard Hayes Nada Marketing PO Box 12 Gordon Australia 2072 Tel: +(61-2) 9412 4367 Fax: +(61-2) 9412 4920 Mob: +(61) 0414 618 425 www.nada.com.au -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html ---------------------------------------------------------------------- IMPORTANT NOTICES This email (including any documents referred to in, or attached, to this email) may contain information that is personal, confidential or the subject of copyright or other proprietary rights in favour of Aristocrat, its affiliates or third parties. This email is intended only for the named addressee. Any privacy, confidence, copyright or other proprietary rights in favour of Aristocrat, its affiliates or third parties, is not lost because this email was sent to you by mistake. If you received this email by mistake you should: (i) not copy, disclose, distribute or otherwise use it, or its contents, without the consent of Aristocrat or the owner of the relevant rights; (ii) let us know of the mistake by reply email or by telephone (+61 2 9413 6300); and (iii) delete it from your system and destroy all copies. Any personal information contained in this email must be handled in accordance with applicable privacy laws. Electronic and internet communications can be interfered with or affected by viruses and other defects. As a result, such communications may not be successfully received or, if received, may cause interference with the integrity of receiving, processing or related systems (including hardware, software and data or information on, or using, that hardware or software). Aristocrat gives no assurances in relation to these matters. If you have any doubts about the veracity or integrity of any electronic communication we appear to have sent you, please call +61 2 9413 6300 for clarification. -- SLUG - Sydney Linux User's Group Mailing List - http://slug.org.au/ Subscription info and FAQs: http://slug.org.au/faq/mailinglists.html
