Kickstarter "Crystal Board: FPGA - Arduino - ARM SoC in a single device"

[Rasz]

>plus $30 for source code

dev board with no code?
not to mention there is no documentation for Rockchip at all

Edit:

Creator Red Crystal >I did also try external HDD via USB 2.0. The transfer rate was around 40 - 50MB/s

thats the fastest USB 2.0 HDD in the world, wonder where else project creator was creative with numbers

[BBQ]

Well what would be a sensible interface between the ARM chip and the FPGA?

RK3188 connectivity:

USB 2.0
HSIC
I2S
GPS
UART
SPI
MAC (RMII)
SDIO 3.0
I2C
HSADC TS I/F (10 bit)
GPIO (128x)

Some memory interfaces
SRAM, DDR

[mikeselectricstuff]

Well what would be a sensible interface between the ARM chip and the FPGA?

RK3188 connectivity:

USB 2.0
HSIC
I2S
GPS
UART
SPI
MAC (RMII)
SDIO 3.0
I2C
HSADC TS I/F (10 bit)
GPIO (128x)

Some memory interfaces
SRAM, DDR

SRAM should give decent bandwidth & flexibility if it was a seperate interface to the main DRAM of the processor. Even better if you can DMA to/from it.
GPIO, if it was writeable in reasonable sized widths (16 bit) at decent speed, ideally with DMA.
SDIO would be reasonable if not, as you should be able to get a reasonable bandwidth without complex protocol in the FPGA.
 

[BBQ]

Well what would be a sensible interface between the ARM chip and the FPGA?

RK3188 connectivity:

USB 2.0
HSIC
I2S
GPS
UART
SPI
MAC (RMII)
SDIO 3.0
I2C
HSADC TS I/F (10 bit)
GPIO (128x)

Some memory interfaces
SRAM, DDR

SRAM should give decent bandwidth & flexibility if it was a seperate interface to the main DRAM of the processor. Even better if you can DMA to/from it.
GPIO, if it was writeable in reasonable sized widths (16 bit) at decent speed, ideally with DMA.
SDIO would be reasonable if not, as you should be able to get a reasonable bandwidth without complex protocol in the FPGA.

There is a DMA controller in it using AXI interface, which is a part of the AMBA interconnect.
How much hassle that is to implement is another question, i guess it is made just for stuff like this.

Anyway, no one got hurt and we all learned something hopefully.

https://github.com/OLIMEX/OLINUXINO/blob/master/HARDWARE/RK3188-PDFs/Rockchip%20RK3188%20brief%20v1.0.pdf

[joelby]

I have, honest 
Is there anything you could recommend for a beginner to FGPAs? In maybe the sub £100 range?

Have a look at my list of cheap FPGA development boards for a great big list and some general recommendations. I usually advise getting a board that has some interesting stuff on it like DDR memory, 100/1000 Mbit Ethernet and HDMI - the things you generally can't use with a cheap microcontroller and will keep you busy for a while.

For an absolute beginner I might recommend the Digilent Nexys 2, only because there's a decent beginner book that has examples for it - FPGA Prototyping by Verilog/VHDL Examples (though the book is not cheap!). Or maybe a Digilent Basys 2 or Papilio One and follow the Hamsterworks FPGA Course.

Once you've mastered the basics and the software, you'll be able to use any dev board given the schematics and some data sheets.

[Marco]

I'm keeping an eye on Parallela, if those boards work out well it's a pretty awesome FPGA development board for the price.

[Stonent]

I wonder if there was a trademark issue? Red Crystal is a trademark owned by the International Red Cross, used a lot I think in the hot areas of Israel/Palestine to remove any religious overtones of their service.