I2C/GPIO Multiple 1-wire sensors and PWM outputs - Raspberry Pi Forums
a while ago friend on mine gave me model b board , couldn't think of it. after installing 20u server rack @ home (...yeah yeah) , realizing didn't choose housing because of datacenter grade climate management , not wanting bolt 8" car radiator fans onto front of rack decided use bunch of high cfm 140mm fans grouped in few clusters attached pwm speed knob thing got years ago.
theoretically fine having manually turn down when house cold , turn when house hot (or machines idling vs. full load) save power gets annoying fast. instead of buying 1 of silly usb auto fan speed thingy thingies why not use raspberry pi have laying around , turn host app can monitor temperatures throughout rack , adjust pwm duty cycle of fan clusters automatically , hey while @ output logdata can parsed web app... , maybe restful interface send commands (okay okay i'm running away myself).
here's questions come in, have little experience ics , i2cs (but hey supposed educational tool right?) , not sure best options are.
need multiple temperature sensor inputs (probably 1-wire ds18b20) far understand can run in parallel on gpio pins of raspberry pi, limited 10 sensors due data lag or something(?) reading on seems imply limit imposed large systems using system radius' of 30m+, if running <1m wires each sensor reasonably use 20 sensors without running serious noise/broken-ness?
i've read there i2cs designed doing (i.e. collecting data lots of 1-wire sensors) have no idea how search 1 of these (the names seem letters... , numbers... ._.) or if found how i'd interpret how use (any links/refs this, if vaguer, awesome!)
1 thing sure of (...i think) need i2c can have multiple pwm outputs control fan groups, again i'm not sure how go looking this, know need multiple outputs... @ least 4 (i can clone output of each pwm output pwm pin of each fan in respective group).
oh! know i'll need use external power supply fans since 12v dc , won't able pull board. run them off spare server psu have laying around i'd power using small board can connect bread board (hopefully later pcb...) can keep fan headers , power them same place.
yeah... sorry question generic, , i'm sure hard answer, i'm coming programmer background has never done i/o interaction , stuff, hardware knowledge doesn't extend beyond knowing how wire led , resistor in circuit (and building printer serial led indicator panel when kid. long time ago)
thanks
theoretically fine having manually turn down when house cold , turn when house hot (or machines idling vs. full load) save power gets annoying fast. instead of buying 1 of silly usb auto fan speed thingy thingies why not use raspberry pi have laying around , turn host app can monitor temperatures throughout rack , adjust pwm duty cycle of fan clusters automatically , hey while @ output logdata can parsed web app... , maybe restful interface send commands (okay okay i'm running away myself).
here's questions come in, have little experience ics , i2cs (but hey supposed educational tool right?) , not sure best options are.
need multiple temperature sensor inputs (probably 1-wire ds18b20) far understand can run in parallel on gpio pins of raspberry pi, limited 10 sensors due data lag or something(?) reading on seems imply limit imposed large systems using system radius' of 30m+, if running <1m wires each sensor reasonably use 20 sensors without running serious noise/broken-ness?
i've read there i2cs designed doing (i.e. collecting data lots of 1-wire sensors) have no idea how search 1 of these (the names seem letters... , numbers... ._.) or if found how i'd interpret how use (any links/refs this, if vaguer, awesome!)
1 thing sure of (...i think) need i2c can have multiple pwm outputs control fan groups, again i'm not sure how go looking this, know need multiple outputs... @ least 4 (i can clone output of each pwm output pwm pin of each fan in respective group).
oh! know i'll need use external power supply fans since 12v dc , won't able pull board. run them off spare server psu have laying around i'd power using small board can connect bread board (hopefully later pcb...) can keep fan headers , power them same place.
yeah... sorry question generic, , i'm sure hard answer, i'm coming programmer background has never done i/o interaction , stuff, hardware knowledge doesn't extend beyond knowing how wire led , resistor in circuit (and building printer serial led indicator panel when kid. long time ago)
thanks
raspberrypi
Comments
Post a Comment