geoffrey oltmans wrote:
Don't some FPGAs have dedicated peripherals on
them for specific
applications
besides the field programmable parts of the silicon?
I can't tell you much about Altera, but some of the dedicated hardware
in Xilinx FPGAs have included:
* block RAMs, 18 or 36 Kbit, in almost all parts
* multipliers or multiply/accumulate blocks in many parts
* very high speed (>1Gbps) serial transceivers in some parts
* a small amount of logic for traditional PCI, in the Spartan-2
* hardware PCIe endpoint logic in the Spartan-6 and Virtex-6
* hardware DDR SDRAM controller in the Spartan-6 and Virtex-6
* PowerPC processor core in some Virtex-4 and Virtex-5 parts
* 10/100/1000 Ethernet MAC in some Virtex-5 and Virtex-6 parts
For details, such as which parts have how many of what hardware blocks,
you'll have to check the datasheets.
Generally they only put in hardware blocks for things that can't be
implemented reasonably efficiently in the fabric. I consider the
10/100/1000 Ethernet MAC to be an exception to that rule of thumb.
Certainly if you want the kinds of traditional peripherals found in
early microcomputers (GPIO, timers, UARTs, video display controllers),
those will have to be in the fabric.
Eric