The second RaspFPGA mezzanine board for Raspberry Pi

This is the second version of the extension card for Raspberry Pi. As the previous one, this circuit connects all GPIO pins of Raspberry Pi to the FPGA chip. I've made a few modifications. Version 2 uses Spartan6 instead of Spartan3, it has 64MB of SDRAM and a small flash memory to store FPPGA configuration. It still leaves all remaining inputs/outputs pins of FPGA for the final user. Now the pin available are less than before because SDRAM occupies many of them. To do not loose this feature one can choose between having SDRAM or having all GPIO available. The choice is done by soldering jumpers in the appropriate places.

Pic. 1 - RaspFPGA v2 board.

The circuit is mechanically and electrically compatible with LCD TFTDisp 4 RaspPAR design published on my blog in March. It contains 25MHz clock source for FPGA, USB to RS232 converter and real time module.

4th Scientific Day of the School of Science and Technology

On the 11th of June I will present a poster about optomechanics during poster session in Palazzo Ducale of University of Camerino. The session starts at 10am. Details of the event one can find at 14th Scientific Day Official Poster.

Pic. 1 - Scientific poster - optomechanics.

Lessons of FPGA

La prima lezione

Esercizio 1 in Italian
Slides 1

La seconda lezione

Esercizio 4 in Italian
Esercizio 5 in Italian
Slides 2

La terza lezione

Esercizio 6 in Italian
Esercizio 2 in Italian
Slides 3

Brushless DC motor of HDD with Arduino

I present a driver for hard drive disk motor based on Arduino and three discreet half H-bridges mounted on proto PCB. Power supply voltage is 12V and current consumption is around 500mA.

Rys. 1 - Theory of driving three phase motor if you use a driver with high-Z output state.

During my first attempt I used L289 chip and I achieved maximal rotary speed around 2900RPM. Using the circuit presented on Rys. 2. I reached the same speed until I was using a simple driving scheme. It means with one phase which breaks the motor. After an upgrade to the scheme from Rys. 1. the rotary speed increased to 7500RPM. Theory, hardware and software are described very well one the website http://elabz.com/.

Rys. 2 - Electric scheme of half H-bridge I used.

Arduino libraries:

BLDC motor Arduino library v0.2

PID in LabView FPGA

RaspFPGA mezzanine board for Raspberry Pi

I present to you an extension card for Raspberry Pi. This circuit connects all GPIO pins of Raspberry Pi to Spartan3 FPGA chip and leaves all remaining inputs/outputs pins of FPGA for the final user. I used Spartan3AN chip which can be configured from internal flash memory at start up or by SPI from Raspberry Pi.

The circuit is mechanically and electrically compatible with LCD TFTDisp 4 RaspPAR design published on my blog in March. It contains 25MHz clock source for FPGA, USB to RS232 converter and real time module. I share this piece of hardware with community as OpenHardware.

RaspFPGA-E6 v1.1_4MBEcho.zip

Milling models gallery

Below I paste all elements I've done at PCNC-1100 milling machine during three years at the University of Nicolaus Copernicus.

Rys. 1 - Breadboard for BEC group

Rys. 2 - CB radio holder for my car

Rys. 3 - CB radio holder for my car (folded)

Rys. 4 - Heatsink gasket

Rys. 5 - Optical bench for Coherent laser

Rys. 6 - Heat sink for laser chiller

Rys. 7 - Cover complementary to the previous heat sink

Rys. 8 - Laser chiller (assembly)

Rys. 9 - Optical breadboard

Rys. 10 - Precise optical holder

Rys. 11 - Front panel of an audio amplifier (front)

Rys. 12 - Front panel of an audio amplifier (section)

Rys. 13 - Front panel of an audio amplifier (back)

Rys. 14 - Doughnut shaped PBC

Rys. 15 - Radio frequency amplifier case

Rys. 16 - Half/quarter waveplate rotary motorized mount (assembly)

Rys. 17 - Half/quarter waveplate rotary motorized mount (body)

Rys. 18 - Half/quarter waveplate rotary motorized mount (pattern for milling)

Rys. 19 - Half/quarter waveplate rotary motorized mount (cover)

Rys. 20 - Stepper motor driver front panel

Rys. 21 - Water tank walls

Rys. 22 - Laser holder for HP pen plotter

Rys. 23 - Laser holder for HP pen plotter