search for: rs232c

Hello One our customer has two Linux HP-branded servers powered from "clasic" APC Smart-UPS 2200 RM 2U (p/n SUA2200RMI2U). It is connected to first server via RS232c port with APC-branded cable. We have installed NUT 2.6.4 with apcsmart driver. This setup works fine for months. Two weeks ago all the hardware powered from the UPS started to switch off occasionally while on line power. The UPS switchs off too and need to be turn on manually. No any warnings o...

...mes Bean" <james@hdcs.com.au> > Has anyone every setup an external open/close relay, off say a serial > interface, and have an extension trigger the relay? The following will do the trick. Just add a 5vdc solid state relay ('cause you can't sink too much current out of the RS232C port). Substitute "2", "4" or "6" in the code below to turn on either DTR, RTS or both signals. "0" for off. Change SWDEV in the lpswitch.h file to be the serial port you intend to use for the relay. I'm using some optically isolated relays I found in t...

...ogram on this little computer device (>100.00) that was "made" for I/O control. It can do all kinds of things pseudo autonomously and feed back the info to the PC. d) X10 have several interfaces for PC's. I like a little one called the "Firecracker" interface. It uses an RS232C line and can control devices by sending radio signals from it to a reciever module that is plugged into a wall socket. It then embeds the cammands you sent it into the electrical circuits in your home. Another module then plugs into the wall somewhere and you plug devices into it. The little wall m...

...t units that I know for a fact have the old-fashioned single-pin dumb interface. And if they're still selling *that* kind of obsolete crap, I have to think maybe there are still SPSes in the world. 1b: Is the SPS in fact dead as a technical category? If not, why not? Oh, and this, too: 1c: RS232C, on consumer devices, in 2009? Ferfuckssake, *why*? It's not like USB chips are expensive or anything. I know all about this from GPS-land, actually; pl2303s are so cheap that even if the vendors wanted to retread their RS232 designs, the cost of goods to refit them with USB-to-serial conver...

> If you just want to control a couple of digital points this hardware may > be overkill, but it is cool stuff. For smaller implementations you can just use the outbound control lines (DTR & RTS) on an RS232C port. That can give you control of two on/off devices. They only sink about 20ma so isolate them with a solid state relay or something. A C program to turn on/off is fairly trivial and run it from AGI. I don't want to clutter the list with code but I can supply if anyone needs it. dbc. -- Dav...

Hi, I am trying to make a program in C to communicate with a temperature sensor over my serial port that uses RS-485 and is a half duplex. I am however having trouble getting the device into RS-485 mode, is it possible to use RS-485 mode in Centos 6.5 or does it only support RS-232 mode?

.../* * lpon Lineprinter ON * *** test program only ** * * (c) David Cook, 1994 * * Set signlal lines on serial port to turn on 5vdc * signal. Used for solid-state relay (low current * draw on RS232C port) to switch high voltage/high * current load for printer. * * Part of an intelligent print spooler to only power * on/off high draw printer when required. * * Usage: lpon<device> <bits to set> * F...

I recently bought a new UPS, and I''m attempting to use nut to monitor it. Following setup instructions everything seemed to go well until it came to testing the connection, which failed. There is just one serial connector on the computer, so I set it to monitor /dev/ttyS0. Either that is wrong, or communication is failing. I''ve been told to try minicom to monitor it,

I think the time for me to get involved in NUT documentation has come again. Late last week I had to buy a UPS under time pressure. The Eaton unit that thus project gifted me with in 2006(?) died during a severe thunderstorm watch, so it was off to MicroCenter to get a replacement pronto. I wound up buying an APC BN700MC. It was what they had in the performance range I needed. The removable