November 30, 2014
Of the recent Pi boards I’ve made I think UserPort is probably my favourite. It’s a mimic of the BBC’s micros digital User Port and Analogue Port.
Back in the 80’s (gosh that sounds old) I built many electronic, robotic and other projects using the Beebs digital User Port and Analogue so reproducing their functionality for the Pi was a pleasure.
Digital I/O is provided by a I2C MCP23017 16-channel Port Expander
20W IDC Connector
Analogue Inputs by a 4-channel SPI MCP3004 10-bit ADC.
15W D Connector
4 ADC CH3
7 ADC CH1
12 ADC CH2
15 ADC CH0
Check my other stuff on Tindie
October 31, 2014
We’ve finally managed to find time to list two new boards on Tindie.
The first is RPi-X PIAC which is an experimenter add-on board for small industrial control projects. It feature 4x Relays (Change Over), 4x Opto-Isolated Inputs and 4x Analogue Inputs (0V to 10V). It also has a RS485 serial interface for communicating with industrial networks. You can find them here
The second board is RPiB+ Breakout+ which is a breakout board for the Raspberry PI B+ I/O signals. It features 2x SPI headers, 2x I2C headers, 2x UART headers and 2x GPIO headers. It also has a prototyping area which is useful building your own circuits. It is compatible with the HAT board size and has a EEPROM (currently not fitted) for future HAT configuration. You can find them here
August 18, 2014
Here’s our first RPiB+ HAT compatible board Breakout!+.
August 14, 2014
4 new PCB’s arrived in the post today. These are my first HAT’s (Hardware on Top) for the Raspberry Pi B+.
Top (L-R) – UserPort and Breadboard+, Bottom (L-R) – DIO32 and Breakout!+
All the boards adhere to the standard HAT size and include a ID EEPROM.
UserPort is probably my favourite. It’s a mimic of the BBC’s micros digital User Port and Analogue Port. Digital I/O is provided by a I2C MCP23017 16-channel Port Expander and Analogue Inputs by a 4-channel SPI MCP3004 10-bit ADC.
Breadboard!+ is a reworking of my earlier 170-pin Breadboard module but the extra size for a HAT PCB has allowed the inclusion of a two tactile push switches and three LED’s. As well as these, there’s also 4x Analogue Inputs using a 4-channel MCP3004 10-bit ADC.
DIO32 is a 32-channel Digital I/O board with two MCP23017 I2C Port Expanders.
Breakout!+ allows easy access to the I2C, SPI and UART interfaces and includes a small prototyping area for building circuits on.
Hope to have them on our Tindie store soon🙂
June 26, 2014
I design my first Pi MIDI interface way back in 2012 while I was waiting for my first Pi board to arrive.
It’s went through several revisions since then and now looks like this:
The circuit is now completely 5V as per the original MIDI specification but the MIDI IN is 3.3V compatible with the Pi via a voltage divider circuit.
OK that’s the hardware what about the software?
Getting a MIDI 31250 Baud Rate on a Pi is not easy as it should be as 31250 is not a standard Pi baud-rate. But you can trick your Pi into it if you overclock (or rather underclock) the UART clock.
Start a terminal session and type:
sudo nano /boot/config.txt
Add these lines to the end of the file
# Change UART clock to 2441406 for MIDI 31250 baud rate
save and exit.
Once saved reboot your Pi.
Next we need to stop the serial UART being used by Raspbian for the shell console. Check my previous post “MiniPIiio RS232 set-up” on how to do this.
Finally we need to add the following to “cmdline.txt”
After doing all of this we should be ready to connect a MIDI keyboard or synth to our Pi.
Again I hope to have it stocked in out our store on Tindie soon:
June 24, 2014
Here’s a photo of a finished RPi-X PIAC experimenter module:
OK what does PIAC stand for?
PIAC = Pi Industrial Automotive Controller
It’s a Pi expansion shield that has 4x Change Over (CO) relays, 4x Opto Isolated Digital inputs and 4x 0V to 10V Analogue Inputs. There’s also a RS485 interface to communicate with industrial networks.
You can use it to learn about industrial control or perhaps even use it on your own small control projects.
I hope to have it stocked in our Tindie store soon:
May 13, 2014
Another box of new boards arrived from DirtyPCBs.com today.
In the box where 4, yes 4 sets of PCB’s.
In the photo, the big PCB at the back is RPi-X PIAC. On the photo front row, on the left is MiniPiio LED Breakout, in the centre is MiniPiio BOP4 and to the right is MiniPiio PWM16
RPi-X PIAC is our latest RPi-X experimenter board. The acronym IAC is commonly used to describe an industrial automation and control system and adding a P in this case makes it a Pi Industrial Automation and Control🙂
PIAC has 4x SPCO Relays rated at 2A, 4x opto-isolated digital inputs, 4x 0-10V Analogue inputs and finally a RS485 communications port. So with the RPi-X PIAC you can learn about industrial control or perhaps use it for your own small industrial project.
MiniPiio LED Breakout uses the popular MAX7219 8-digit (64x LED) LED display driver chip to breakout all 64 LED outputs to 8 rows of pin headers. From these pin headers you can plug in individual LED’s to make whatever LED display layout you want. It’s a shame its not Christmas as I think it would make a great blinky LED Christmas tree🙂
MiniPiio BOP4 or Board of Pots (or should that be “Bored of Pots”) has 4 potentiometers (3x rotary and 1x slider) and connects them to a 4-ch MAX3004 ADC. I think it will a great physical user interface. It’ll probably make a great companion to the LED/Switch MiniPiio SimpleIO we showed off a few months back. Of all the new boards I think this is my favourite🙂
The final new PCB, is MiniPiio PWM16. I think its name gives it away. It’s a hardware based 16-channel PWM add-on board using the popular PCA9685.
As always you’ll find them on my Tindie store in the next few days.