coolpi

a really simple cooling program for the Raspberry Pi, written in C.

Dependence

This program is base on wiringPi. Before your trying to build it, do check the installation of wiringPi with the command below.

gpio -v

If everything is fine, you are likely to see the message below.

gpio version: 2.46
Copyright (c) 2012-2018 Gordon Henderson
This is free software with ABSOLUTELY NO WARRANTY.
For details type: gpio -warranty

Raspberry Pi Details:
  Type: Pi 3+, Revision: 03, Memory: 1024MB, Maker: Sony 
  * Device tree is enabled.
  *--> Raspberry Pi 3 Model B Plus Rev 1.3
  * This Raspberry Pi supports user-level GPIO access.

Hardware

Pin Number

BCM	WiringPi	Name	Phys	ical	Name	WiringPi	BCM
		3.3v	1	2	5v
2	8	SDA.1	3	4	5v
3	9	SCL.1	5	6	0v
4	7	GPIO. 7	7	8	TxD	15	14
		0v	9	10	RxD	16	15
17	0	GPIO. 0	11	12	GPIO. 1	1	18
27	2	GPIO. 2	13	14	0v
22	3	GPIO. 3	15	16	GPIO. 4	4	23
		3.3v	17	18	GPIO. 5	5	24
10	12	MOSI	19	20	0v
9	13	MISO	21	22	GPIO. 6	6	25
11	14	SCLK	23	24	CE0	10	8
		0v	25	26	CE1	11	7
0	30	SDA.0	27	28	SCL.0	31	1
5	21	GPIO.21	29	30	0v
6	22	GPIO.22	31	32	GPIO.26	26	12
13	23	GPIO.23	33	34	0v
19	24	GPIO.24	35	36	GPIO.27	27	16
26	25	GPIO.25	37	38	GPIO.28	28	20
			39	40	GPIO.29	29	21

Wiring

The default wiringPi pin that connected to the base of transistor is 4, you can custom it by write your own configure file.

Build && install

Easy with a few commad:

git clone https://github.com/ChanthMiao/coolpi.git
cd coolpi && make
sudo make install

Usage

Well, now the the coolpi should be running as a linux daemon, if everything is ok. This program has maintain a set of defalut configure values that passed my personal test. Yet, you may offer a set of customed values through writting your own configure file.

The comments is not supported in the configure file. I offer a sample named '/etc/coolpi/sample.json'.

{
    "con": 4,
    "upperLimit": 48000,
    "onMsec": 20000,
    "lowerLimit": 44000,
    "offMsec": 2000,
    "waitMsec": 1000
}

option	what is it
con	wiringPi pin that connected to the base of transistor
upperLimit	threshold for turning on the fan ($^\circ C$/k)
onMsec	continuous running time of the fan on (ms)
lowerLimit	threshold for turning on the fan ($^\circ C$/k)
offMsec	continuous waiting time of the fan off (ms)
waitMsec	continuous waiting time of the fan when the temperature is in the middle segment (ms)

Then, modify the line 8 of '/lib/systemd/system/coolpi.service' to the content blow:

ExecStart=/usr/local/bin/coolpi -c /etc/coolpi/$YOUR_CONFIGURE

Reload the '/lib/systemd/system/coolpi.service' with command here:

sudo systemctl daemon-reload

All thing done, have fun with you raspberry Pi 3B+ !

Note

• If you want to uninstall the coolpi, just one command is needed.

  sudo /etc/coolpi/uninstall.sh

• Only after your modification of '/lib/systemd/system/coolpi.service', the command "sudo systemctl daemon-reload" is needed. If you just want reload your customed configure file, do run the command blow:

  sudo systemctl reload coolpi.service