@redplc/node-red-rpi-gpio

Node-RED nodes for Raspberry Pi GPIO using with redPlc nodes.

Nodes

• rpi-gpio-in: Reads GPIO inputs and store in boolean array.
• rpi-gpio-out: Sets GPIO outputs from boolean array.
• rpi-gpio-pwm: Sets GPIO pwm duty cycles from number array.
• rpi-gpio-cnt: Counts GPIO inputs pulse and store in number array.

Usage

• Install redPlc nodes.
• Use redPlc s-inject node for trigger update.
• Connect to first output on s-inject node.
• Daisy chain nodes in series.
• For logical operations use redPlc nodes.
• Data is exchanged with global context variable arrays.
• Array index is equal gpio number for easy handling.
• Select different gpio pins for input, output and pwm.
• For open inputs select pull down/up resistors.
• This node works on Raspberry Pi with 32bit or 64bit OS.
• Check with raspi-config for alternate functions on GPIO.

Array Index Mapping

Index	Funct.	Pin	Pin	Funct.	Index
	3V3	1	2	5V
2	GPIO02	3	4	5V
3	GPIO03	5	6	GND
4	GPIO04	7	8	GPIO14	14
	GND	9	10	GPIO15	15
17	GPIO17	11	12	GPIO18	18
27	GPIO27	13	14	GND
22	GPIO22	15	16	GPIO23	23
	3V3	17	18	GPIO24	24
10	GPIO10	19	20	GND
9	GPIO09	21	22	GPIO25	25
11	GPIO11	23	24	GPIO08	8
	GND	25	26	GPIO07	7
		27	28
5	GPIO05	29	30	GND
6	GPIO06	31	32	GPIO12	12
13	GPIO13	33	34	GND
19	GPIO19	35	36	GPIO16	15
26	GPIO26	37	38	GPIO20	20
	GND	39	40	GPIO21	21

Examples

Example 1

This example is a self holding circuit used for push buttons.
Led turns on, if switch GPIO21 is closed.
Led turns off, if switch GPIO20 is closed.

• Connect LED with resistor (~220 Ohms) to GPIO26 and ground pin.
• Connect switches to GPIO20 and GPIO21 and ground pin.
• Select GPIO20 and GPIO21 as pullup inputs.
  
• Select GPIO26 as output.
  

Example 2

This example sets led brightness to 25%, 50% or 100% with switches.

• Connect LED with resistor (~220 Ohms) to GPIO26 and ground pin.
• Connect switches to GPIO16, GPIO20 and GPIO21 and ground pin.
• Select GPIO16, GPIO20 and GPIO21 as pullup inputs.
  
• Select GPIO26 as pwm.