LED Matrix is a powerful FPGA-based development board, ideal to carry out educational experiments, but also professional projects. It has FPGA (XC6SL9) Xilinx Spartan 6 of 102 I / O, 11000 Flip-Flop and 32 BlockRAM. Of the 102 I / O, 62 are available for general use, while the rest are assigned to dedicated functions, such as: USB serial, EEPROM memory, SD card, Boot Flash, etc.
The FT2232HL the FTDI chip manages the serial interface and allows to obtain, by a single USB 2.0 connection, two virtual serial ports that actually at the hardware level are a high-speed serial interface and an 8-bit parallel. This allows to use a serial port to load the firmware and the other to acquire the data.
In fact, this board can be programmed directly via USB thanks to the preloaded bootloader. Therefore, for the use that the uploaded programs do NOT need to use the Xilinx JTAG cable, with a considerable saving of money and a simplification in the management of the board. Loading "Bitstream" (programs for the FPGA) is via a terminal software available free of charge.
The board is able to handle up to 15 different Bitstream, the launch of which can be chosen by the boot loader directly from the terminal menu.

To immediately test the card, besides the bootloader, LED Matrix is supplied with an application to manage graphic panels with RGB LED dot matrix (max. 4 32x32 panels). Thanks to the FPGA and the parallel processing capabilities (multi-thread), LED Matrix is able to handle animations also fast and run at very high speed programs. The display management via PC, takes place by means of the free software Jinx.

The board can be powered via USB or via an external 5 V power supply, adapter current consumption: 100 mA, dimensions (mm): 89x79.

N.B. graphic panels with RGB LEDs and the power supply are not included (see related products).

Diagram block of the LED board Matrix

L’FPGA

It is a very versatile and a typical device because it can carry out the tasks of microcontrollers and microprocessors, although he is neither one nor the other and is able to adapt to various kinds of tasks thanks to the great flexibility offered by an architecture that is not rigid as that of a microcontroller but consists of a large number of elementary logic devices (logic gates, flip-flops and counters, multiplexers / demultiplexers, encoders and decoders ...) and un'ALU, all linked together using CMOS internal switches in various ways to achieve an infinite number of configurations. The interconnections are "programmed" so as to electrically connect between them the logical devices in order to obtain the desired logic function; also allow the internal logic of entering to the I / O pins.

The processing capabilities of an FPGA is defined with the number of "equivalent gate" i.e. of logic gates corresponding to all the integrated devices (we know that in general the logical devices can be composed with the basic gates NOT, OR, NOR, AND, NAND, XOR). The simplest are about 10 million gate FPGA while the higher performance they arrive at the gate 2 million (corresponding to about 500,000 CD4001 type chip).
Another parameter to consider in the choice of a FPGA is the number of pins of input / output, which in the smaller models is about 50 while in the larger (in BGA packages) comes to 1,000. The ratio of I / O available and equivalent gate is another crucial factor: devices with a few I / O and many logic gates can perform many calculations, but do well in applications where elements to interface are few, while FPGA with many I / Or are fine to manage processes in which the use of acquiring many signals and send as many, or for parallel processing.

The computing unit (ALU) contained in the FPGA is very fast and has clock ranging from 200 MHz up. Compared to using the classic microcontrollers and microprocessors, the FPGA provides benefits that are in the possibility to reconfigure the logic at any time, in the hardware and versatility in the ability to realize also very complex circuits. To define the logic that I want to program the FPGA need a program that "translates" the circuit wiring diagram in a programming binary file which is then transferred into the FPGA boot memory via a dedicated programmer (in the case of the Spartan 6 talk JTAG).

Documentation and useful links