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When does a CPLD start working on a FPGA?
CPLDs start working as soon as they are powered up Since FPGA has to load configuration data from external ROM and setup the fabric before it can start functioning, there is a time delay between power ON and FPGA starts working. The time delay can be as large as several tens of milliseconds. Non-volatile.
Can a FPGA change its circuit while running?
FPGAs can change their circuit even while running! (Since it is just a matter of updating LUTs with different content) This is called Partial Reconfiguration, and is very useful when FPGAs need to keep running a design and at the same time update the it with different design as per requirement. This feature is widely used in Accelerated Computing.
Is the architecture of a FPGA publicly released?
While the exact FPGA architecture is not publicly released by manufacturers, we can still get higher level architecture, which will help in understanding FPGAs and its working. A high-level example from Xilinx’s documentation is below.
What’s the maximum number of flip flops in a FPGA?
Each macrocell contains 1 Flip-Flop and PLA array of Sum of Products which users can utilize to create to combinatorial or sequential logic. So the maximum number of Flip Flops available in CoolRunner-II CLPD (XC2C512) is 512! (Remember this number, we will compare it with a number of Flip Flops in FPGAs)
What happens when a FPGA is powered up?
As mentioned before, FPGAs are LUT based. When an FPGA is powered up, the device is always blank. A special circuit called Configuration Circuit is present which reads the configuration data from an external ROM, and configures the LUTs as per user’s design present in the external ROM.
Which is better a GPU or a FPGA?
The world of high performance computing is a rapidly evolving field of study. Many options are open to businesses when designing a product. GPUs can provide astonishing performance using the hundreds of cores available. On the other hand, FPGAs can provide computational acceleration to many signal and data processing applications.
How many CLBs are in a 7 Series FPGA?
For the brave, Xilinx published a lot of details in Xilinx User Guide on 7 Series FPGAs Configurable Logic Block. FPGAs can contain even millions of CLBs in a single device!
What’s the difference between EEPROM and FPGA?
It is a programmable logic device that is based on Electrically Erasable Programmable Read Only Memory or EEPROM, has a comparatively less complex architecture as compared to FPGA, and is much more suitable in small gate count designs such as glue-logic.
What kind of signalling is used in a CPLD?
The common differential signalling standards for CPLDs and FPGAs are low voltage differential signaling (LVDS), current mode logic (CML), and low voltage positive emitter coupled logic (LVPECL). You’ll need to program your IC and design your schematic /layout around the desired signalling standard.