From mboxrd@z Thu Jan 1 00:00:00 1970 To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> In-reply-to: Your message of "Fri, 29 Jul 2011 06:44:09 PDT." References: Date: Fri, 29 Jul 2011 13:25:29 -0700 From: Bakul Shah Message-Id: <20110729202529.19D6EB827@mail.bitblocks.com> Subject: Re: [9fans] Maybe a weird Plan 9 project. Topicbox-Message-UUID: 080f5004-ead7-11e9-9d60-3106f5b1d025 On Fri, 29 Jul 2011 06:44:09 PDT David Leimbach wrote: > > I was outside watering plants this morning that seem to be proof of my > "not-so-green thumb" I have for gardening and was thinking of an interesting > home-automation use for Plan 9. > > What I'd like to do is get the following: > > 1. Moisture sensor I can embed in some potted plant soil, and read from Plan 9 > 2. Tubing. > 3. Pump I can control from Plan 9 based on moisture feedback. > 4. Perhaps a rain bucket water source. > > Anyone else using Plan 9 for automated gardening? I was thinking this could > be the use for Plan 9 on my guruplug. > > Any ideas how best to achieve this? If some stuff isn't supported by Plan > 9, I'm willing to investigate the writing of drivers to make it work > properly. > > Just trying to find new ways to be lazy I suppose. I just used X-10 for years for watering (periodic, no moisture sensing -- plants are very forgiving). I still use that old CP-290 for lights, laser printer on/off etc. One of these day its ctl program needs to morph into a 9p server. You can build a very cheap moisture sensor with two electrodes and some plaster of paris [make it small so that it dries quickly]. Calibrate resistance as a function of moisture. May be an Arduino to measure the resistance and control a relay to power a solenoid valve? May be it can talk 9p. That said, I am very interested in an el-cheapo building block that talks 9p over USB and can connect to various sensor inputs, D2A and PWM outputs to control steppers etc. It should mostly sleep to conserve power. Even nicer if it can be wireless. el-cheapo == under $10 in small quantities!