i'm a beginner tryin to build some application with a scraped xc2v3000
after generating a bit file with the ISE,i try to configure the FPGA ;iMPACT recognizes it but it looks that there is no erase or write option active
consider that: my board is home made the device is a virtex2 that as you know better than me it has a 1,5V core,but my programming cable (digilent) is rated down to 1,8V
Virtex 2-FPGAs, as well as all other (currently available) FPGAs from Xilinx are SRAM-based. There's no flash memory to "erase" or "write" inside the FPGA. It loses its configuration when you power it off.
Of course that means you have to load the FPGA with iMPACT (or a configuration PROM, or external microcontroller, if you have something like that on the board) every time you power up the board, otherwise the FPGA won't do anything.
HTH, Sean
--
My email address is only valid until the end of the month.
Go figure what the address is going to be after that...
Drunk is the right state to use iMPACT. For example, if you go back and forth between writing .bit's into FPGAs and .mcs's into Xilinx config proms, you will want to stab someone each time you forget to turn ON erase/verify/use-internal-config-clock for the PROM because iMPACT mysteriously forgot those settings... AGAIN
One of numerous quirks... In ISE8.2 SP3, iMPACT just crashes if you dare to rename or move the bitfile that is currently assigned.
And has anyone noticed that it uses two different file selection boxes? If you detect the JTAG-chain and it finds a device, it prompts you automatically to select a corresponding bitfile. The selection box is "old style"; for example you can't enter network paths manually, and the drop-down list for drive selection only shows the drive letters, not the names. So imagine you have 4 or 5 network shares mapped and you just cannot remember if the one the bitfile is on was X:, Y: or Z:... Very annoying. But if you assign a new bitfile later on (e.g. by right-clicking the device and selecting "Assign new bitfile"), you get a completely different file selection box, the standard one more or less all Windows applications use now. So obviously two different people worked on that, two different codes for the same thing. Not a "problem" per se, but it makes you wonder... if things like that are common in other parts of ISE, it might explain certain "This only works when I do it like this but not when I do it like that"-effects.
--
My email address is only valid until the end of the month.
Go figure what the address is going to be after that...
That's probably related to the fact that you can't assign a new one. The menu option is there, and if you select it you get the bit/bmm/etc dialog, but if you select the old .bit file, "remove" stays grayed out. I end up rediscovering the chain to have another go at assigning a file. Since it doesn't really remember my settings for the prom or cpld anyway it hardly matters...
And considering the tool can't remember settings WHILE it's running, why is it so rabid about having you work within an open "project" which it wants to save for you?
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.