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I see the word pi and wiring. Any of your people have knowledge around embedded software for a cars. In car computer. I want to feed my pi with the data as while I was modifying the car I had to take out the in car little box. It will need some coding I'm clear but I've been learning c for a while and thinking a project like this could boost my knowledge. (My knowledge is basic.) If anyone has this knowledge I would love a direct back of forth exchange. Also as I'm soon moving to saltash meetings do you have local to there? Warm regards James Ambrose > On 16 Feb 2017, at 19:37, Gordon Henderson via list <list@xxxxxxxxxxxxx> wrote: > >> On Thu, 16 Feb 2017, Tremayne, Steve via list wrote: >> >> Gordon, > > You get a higher quality reply if you email me directly rather than via the list > ;-) > >> I was "fiddling" with a Ras Pi Zero and a 1-wire temp sensor yesterday... >> >> Does your Wiring Pi deal with 1-wire? I got no search results from the site, so >> I'm presuming not? > > 1-wire is handled very well by the Linux kernel and its owfs (one-wire filing > system), so there's no need for me to write anything for something that's already > there. > > However, for the common ds18b20 1-wire temperature sensors, I've created a pin > wrapper for them to better integrate them into the wiringPi world. > > You'll need to install the latest wiringPi from source though. > > http://wiringpi.com/download-and-install/ > > then run: > > sudo raspi-config > > go through the menus and enable 1-wire. Plug in the sensor - it's fixed to > bcm_gpio pin 4 (physical pin 7) then > > ls /sys/bus/w1/devices > > If you see a 28-????? file, then the ds18b20 is present. You can cat this > file/w1_slave - e.g.: > > $ cat /sys/bus/w1/devices/28-0000053af458/w1_slave > f6 00 4b 46 7f ff 0a 10 d6 : crc=d6 YES > f6 00 4b 46 7f ff 0a 10 d6 t=15375 > > your filename will be different from mine - each device has a unique 64-bit ID and > mine is: 0000053af458. > > In the output above, YES means a good read and t=15375 is the temperature times > 1000. Remember these are +/- 1ÂC devices, so round and truncate appropriately. > > With the latest wiringPi: > > $ gpio -x ds18b20:100:0000053af458 aread 100 > 154 > > means 15.4ÂC. > > In a C program: > > #include <ds18b20.h> > > int temp10 ; > if (ds18b20Setup (pinBase, "0000053af458") < 0) > .. something went wrong exit (1) ; > temp10 = analogRead (pinBase) ; > > returns the temperature times 10 as an integer. > > Reading takes about 3/4 a second. > >> It's been a while since I've really done much "fiddling" with electronics, so >> I'm finding more rust on my brain than I thought - so, if 1-wire is handled by >> I2C / SPI, then apologies... I'll just go and RTFM... > > It's handled directly. Use BCM_GPIO pin 4 and off you go. > > Gordon > -- > The Mailing List for the Devon & Cornwall LUG > https://mailman.dclug.org.uk/listinfo/list > FAQ: http://www.dcglug.org.uk/listfaq -- The Mailing List for the Devon & Cornwall LUG https://mailman.dclug.org.uk/listinfo/list FAQ: http://www.dcglug.org.uk/listfaq