Raspberry Pi B+ GPIO compatibility

There are many plug in boards for the Raspberry Pi model B (2 x 13 pin connector) which are now not compatible with the Model B+ as this has 2 x 20 pin connector. Even if they plug in, they can interfere with some of the components as the position of the GPIO has moved.

Fortunately the entire Custard Pi range is compatible with the Model A, B and the Model B+.

Mains Switch Widget for Home Automation

The Mains Switch Widget allows the user to switch 230V or 110V mains ON and OFF to mains powered devices from microcontrollers like the PIC and the Arduino or from single board computers like the Raspberry Pi and the Beaglebone. All the safety requirements are designed-in to prevent any faults resulting in a fire. A plastic enclosure is supplied to prevent the user from accidentally touching the mains voltage.

Fixing switch bounce in firmware

I have been involved in many products where a poor understanding of switch bounce has led to a design that had problems in the field. To learn how to deal with this the engineer has to understand exactly what switch bounce is. Although I refer to this as switch bounce, it relates to reading any input.

Custard Pi 8 project for the Raspberry Pi - Electronic Dice

This project is ideal for schools and colleges to demonstrate using the Raspberry Pi in an electronics project. It uses the GPIO and also can be used to teach students to solder conventional and SMT devices as well as wires.

Custom metal enclosures for products - an alternative to injection moulding

Many designers rush to injection moulding when designing enclosures for electronic products. Often there are many other alternative options. Here we consider custom metal enclosures with a case study  using the PAT-IT Portable Appliance Tester. More examples can be seen in the book "From Prototype to Product - a Practical Guide for Electronic Engineers".

Weighing scales project using a Load Cell and Custard Pi 3

This is an experimental project using a Load Cell and the Custard pi 3 to produce weighing scales. A circuit to amplify the signal and sample code is also presented.

Custard Pi 7 - Hardware Hackers interface to the Raspberry Pi

This post presents information about the Custard Pi 7. This has relay and open collector outputs, 8 bit general purpose pins that can be programmed as inputs and outputs, 4 analogue inputs and 1 analogue output and an LCD interface. It also has a prototyping area which icludes layout for a SMT IC. All of this is provided using the I2C interface which leaves all the rest of the pins on the GPIO to be used for other purposes if required.