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What is FPGA bootloader?
The TinyFPGA USB Bootloader is an open source IP for programming FPGAs without extra USB interface chips. It implements a USB virtual serial port to SPI flash bridge on the FPGA fabric itself. Commands to boot into the user configuration or access the SPI flash are all transfered over this interface.
What is a CPLD an FPGA describe why they might be used in an embedded system?
CPLD is suited for control circuit because they have more combinational circuit. Timing reports will be different if same code is synthesized many times. Timing reports will be same result. FPGA can be used to high-end product. CPLD can be used to low-end product.
Why FPGA is more popular than CPLD?
Very small amount of logic resources. Massive amount logic and storage elements, with which incredibly complex circuits can be designed. FPGAs have thousands times more resources! This point alone makes FPGAs more popular than CPLDs.
What is the advantage of an FPGA over a CPLD?
FPGAs offer more logic flexibility and more sophisticated system features than CPLDs: clock management, on-chip RAM, DSP functions, (multipliers), and even on-chip microprocessors and Multi-Gigabit Transceivers.
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.
Is the same U-Boot branch used for all FPGA devices?
The same U-Boot branch is used for all SoC FPGA devices: Cyclone V SoC, Arria V SoC, Arria 10 SoC, Stratix 10 SoC, Agilex. Does not support custom user settings anymore. Instead all custom user settings must be done directly in U-Boot (device tree, configuration and source code).
Where can I find the bootloader source code?
The bootloader source code was removed from SoC EDS. Instead, the user needs to clone the git trees from https://github.com/altera-opensource/u-boot-socfpga . The same U-Boot branch is used for all SoC FPGA devices: Cyclone V SoC, Arria V SoC, Arria 10 SoC, Stratix 10 SoC, Agilex.
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.