The Custard Pi 5 provides the following benefits for the hobbyist intending to use the GPIO. 1. The board simply plugs into the 26 way GPIO connector. Two power on LEDs are fitted to the 3.3V and 5V rails to confirm correct plug in. 2. The 8 pins of the digital I/O on the Pi are protected from accidental connection of a high voltage. 3. There are screw terminals provided for the 8 I/O to easily connect to external electronics and also to the 3.3V, 5V and 0V pins. The digital pins are: 11, 12, 13, 15, 16, 18, 22 and 7. 4. The 3.3 V and 5 V voltage rails have 100 mA multifuses fitted and are protected from over voltage. 5. This plug-in Custard Pi uses a stackable connector, so that other boards have access to the GPIO pins.

1. CUSTARD PI 5
Breakout board with protection for 8 digital I/O and stackable
connector
21st June 2013
SF Innovations

2. FEATURES
www.sf-innovations.co.uk

3. DIGITAL INPUTS / OUTPUTS
www.sf-innovations.co.uk
8 digital pins
Can be used as inputs or outputs

4. www.sf-innovations.co.uk
PROGRAM TO DEMONSTRATE THE INPUTS
AND OUTPUTS
This program sets up pins 11, 12, 13, 15, 16, 18 as outputs
The 6 output pins each have a 330 ohm resistor and an LED to 0V.

5. DIGITAL INPUTS
www.sf-innovations.co.uk
Pins 22 and 7 are inputs with a pull up resistor.
These pins each have a switch as shown.

6. www.sf-innovations.co.uk
#!/usr/bin/env python
import RPi.GPIO as GPIO
GPIO.setmode(GPIO.BOARD)
# set pins 11, 12, 13, 15, 16 and 18 as outputs
GPIO.setup(11, GPIO.OUT)
GPIO.setup(12, GPIO.OUT)
GPIO.setup(13, GPIO.OUT)
GPIO.setup(15, GPIO.OUT)
GPIO.setup(16, GPIO.OUT)
GPIO.setup(18, GPIO.OUT)
# set pins 22 and 7 as inputs with pull ups
GPIO.setup(22, GPIO.IN, pull_up_down=GPIO.PUD_UP)
GPIO.setup(7, GPIO.IN, pull_up_down=GPIO.PUD_UP)
import time
PYTHON PROGRAM LISTING
Download Python code

7. www.sf-innovations.co.uk
while True:
input_value1=GPIO.input(22) #read pin 22 into input_value1
input_value2=GPIO.input(7) #read pin 7 into input_value2
if input_value1 == False: # if pin 22 goes low due to button being pressed
GPIO.output(11, True) # flash the 6 LEDs in turn
time.sleep(0.5)
GPIO.output(11, False)
time.sleep(0.5)
GPIO.output(12, True)
time.sleep(0.5)
GPIO.output(12, False)
time.sleep(0.5)
GPIO.output(13, True)
time.sleep(0.5)
GPIO.output(13, False)
time.sleep(0.5)
GPIO.output(15, True)
time.sleep(0.5)
PYTHON PROGRAM LISTING

8. www.sf-innovations.co.uk
GPIO.output(15, False)
time.sleep(0.5)
GPIO.output(16, True)
time.sleep(0.5)
GPIO.output(16, False)
time.sleep(0.5)
GPIO.output(18, True)
time.sleep(0.5)
GPIO.output(18, False)
time.sleep(0.5)
if input_value2 == False: #if pin 7 goes LOW due to button
#being pressed
print "good bye" #print "good bye" to screen
GPIO.cleanup() #exit program
import sys
sys.exit()
PYTHON PROGRAM LISTING

9. www.sf-innovations.co.uk
When the switch connected to pin 22 is pressed the program
flashes each of the 6 LEDs in turn
When the switch connected to pin 7 is pressed the program
prints “good bye” to the screen and stops.
Blog dedicated to electronics & Raspberry Pi
Custard Pi 5 available from stockists
Up-to-date info on stockists on website
Further information