Seth's tractor bed controller!

Seth's tractor bed logic and controller, MQTT etc

Peripherals

Inputs:

• DHT11 temperature + humidity sensor
• 5 x Push buttons connected directly to RaspberryPi GPIO pins with 10k pullup resistors

Outputs:

• 4 x Status LEDS; 1 green and 3 yellow.
• 8 x 5v powered relays, capable of switching 220v @ 10A
  • 1 x 12v roof amber beacon
  • 2 x 12v LED headlights
  • 4 x 12v LED roof side lights
  • 1 spare relay (wired with 5v out on rear cable)

All outputs are driven using an MCP23017 expander.

HATs:

• Pimoroni SpeakerPhat

RaspberryPi GPIO

BCM	Raspberry Pi	Mode	Usage
	GPIO #5	Input	Push button 1
	GPIO #6	Input	Push button 2
	GPIO #13	Input	Push button 3
	GPIO #22	Input	DHT11 sensor
	GPIO #25	Input	Push button 4
	GPIO #26	Input	Push button 5

MCP23017 Expander 1

TODO: add documentation, both MCP pin, plus i2c address

MCP Name	MCP Pin	Mode	Usage
GPB0	1	Output
GPB1	2	Output
GPB2	3	Output
GPB3	4	Output
GPB4	5	Output
GPB5	6	Output
GPB6	7	Output
GPB7	8	Output
GPA0	21	Output
GPA1	22	Output
GPA2	23	Output
GPA3	24	Output
GPA4	25	Output
GPA5	26	Output
GPA6	27	Output
GPA7	28	Output

Cable to rear cabin

Colour		Voltage	Relay pin	Purpose
Black		Ground
Red		12v	3	Roof light
Green		12v	4	Roof light
Blue		12v	5	Roof light
Yellow		12v	6	Roof light
White		12v	7	Amber beacon
Brown		5v	8

Cable at front bumper

Colour		Voltage	Relay pin	Purpose
Green/Yellow		Ground
Blue		12v	1	Head light
Brown		5v	2	Head light

MQTT

The unit is fully controllable via MQTT, startup and regular messages are published.

Topic	Type	Purpose	Example payload
tractorbed/{deviceid}/status	Pub	once a minute
tractorbed/{deviceid}/uptime	Pub	seconds since startup	302
tractorbed/{deviceid}/version	Pub
tractorbed/{deviceid}/humidity	Pub	once a minute	61.3
tractorbed/{deviceid}/temperature	Pub	once a minute	22.5
tractorbed/{deviceid}/service/cmnd/reset	Sub
tractorbed/{deviceid}/service/cmnd/localcontrol	Sub		ON or OFF
tractorbed/{deviceid}/service/stat/localcontrol	Pub		ON or OFF
tractorbed/{deviceid}/sounds/play	Sub	Play MP3	sheep
tractorbed/{deviceid}/sounds/playing	Pub		sheep
tractorbed/{deviceid}/sounds/available/all	Pub		ON or OFF
tractorbed/{deviceid}/sounds/available/{dir}	Pub		ON or OFF
tractorbed/{deviceid}/inputs/button1	Pub	Button 1	PRESSED
tractorbed/{deviceid}/inputs/button2	Pub	Button 1	PRESSED
tractorbed/{deviceid}/inputs/button3	Pub	Button 1	PRESSED
tractorbed/{deviceid}/inputs/button4	Pub	Button 1	PRESSED
tractorbed/{deviceid}/inputs/button5	Pub	Button 1	PRESSED
tractorbed/{deviceid}/outputs/cmnd/ledpower	Sub	Shows if local buttons are enabled	ON or OFF
tractorbed/{deviceid}/outputs/stat/ledpower	Pub	Shows if local buttons are enabled	ON or OFF
tractorbed/{deviceid}/outputs/cmnd/led1	Sub		ON or OFF
tractorbed/{deviceid}/outputs/stat/led1	Pub		ON or OFF
tractorbed/{deviceid}/outputs/cmnd/led2	Sub		ON or OFF
tractorbed/{deviceid}/outputs/stat/led2	Pub		ON or OFF
tractorbed/{deviceid}/outputs/cmnd/led3	Sub		ON or OFF
tractorbed/{deviceid}/outputs/stat/led3	Pub		ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay1	Sub	Headlight	ON or OFF
tractorbed/{deviceid}/outputs/stat/relay1	Pub	Headlight	ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay2	Sub	Headlight	ON or OFF
tractorbed/{deviceid}/outputs/stat/relay2	Pub	Headlight	ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay3	Sub		ON or OFF
tractorbed/{deviceid}/outputs/stat/relay3	Pub		ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay4	Sub		ON or OFF
tractorbed/{deviceid}/outputs/stat/relay4	Pub		ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay5	Sub		ON or OFF
tractorbed/{deviceid}/outputs/stat/relay5	Pub		ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay6	Sub		ON or OFF
tractorbed/{deviceid}/outputs/stat/relay6	Pub		ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay7	Sub	Amber roof beacon	ON or OFF
tractorbed/{deviceid}/outputs/stat/relay7	Pub	Amber roof beacon	ON or OFF
tractorbed/{deviceid}/outputs/cmnd/relay8	Sub	Not connected	ON or OFF
tractorbed/{deviceid}/outputs/stat/relay8	Pub	Not connected	ON or OFF

RaspberryPi setup

PI zero setup notes:

• Burn raspbian stretch minimal to a micro sd card
• Connect to HDMI + USB
• Login
• Edit /etc/wpa_supplicant/wpa_supplicant.conf, add in SSID
• Reboot
• Edit /etc/hostname
• Edit /etc/tractordaemon.conf (see tractordaemon-example.conf in repo)

Setup local Ansible environment, on laptop:

virtualenv venv
source venv/bin/activate
pip install -r requirements.txt

Bootstrap it using the included Ansible playbook:

ssh pi@tractorbed.home.nat.ms "mkdir .ssh"
scp ~/.ssh/id_ecdsa.pub pi@tractorbed.home.nat.ms:.ssh/authorized_keys
ansible-playbook -i deploy/hosts deploy/playbooks/tractorbed.yml -u pi -l dev