On Jan 2, 2014, at 2:41 PM, Al Kossow <aek at bitsavers.org> wrote:
On 1/2/14 10:42 AM, Peter C. Wallace wrote:
The Zynq is just way overpriced for what it is.
Unless you need high processor <=> FPGA bandwidth, a Spartan6 and a seperate Arm
chip with simple bus interface is 1/2 the price or less.
Peter Wallace
Mesa Electronics
What is your preferred Arm processor and FPGA interface method these days?
I really like the STM32 series with a parallel interface for anything
that needs some real speed. If you don't need lots of speed, SPI is
pretty good and not too sluggish. STM32F4 goes a long way and packs
a lot of punch.
I like STM32 because their parallel interface is pretty straightforward.
Freescale's Kinetis is similarly good, but as much as I like Freescale
chips, they're quite complex to get off the ground and they often have
an errata list a mile long. TI has some nice parts in their Stellaris
line, but they seem to be axing one of the best ones (which had both a
parallel bus AND a built-in 10/100 PHY, which was great for cutting
board space). I'm also slightly biased against the TI chips because
they often only take 3.3v as a supply (a problem for my low-power RF
projects), but that's not such a bad thing in this context.
The STM32F4DISCOVERY kit is dirt-cheap and comes with an open-source
compatible USB debug device built in. It takes some leg work to get
up and running, though, and there's no real RS232 port on board (you
can use one of FTDI's flying-lead CMOS-level USB->UART cables to attach
to the pins of one of the UARTs, though, which is almost as good). No
Ethernet on that board, though.
- Dave