Hello! I instantiated SDRAM memory in an EDK project, but I don't know what I have to do in order to boot from it. I want to store my instructions and data into it. Does anyone can help me? Thank you! Melissa
SDRAM in EDK
Started by ●October 26, 2005
Reply by ●October 26, 20052005-10-26
"mvetromille" <mvetromille@gmail.com> schrieb im Newsbeitrag news:b1bb368c3bf24200aae1c08000ca3267@localhost.talkaboutelectronicequipment.com...> Hello! I instantiated SDRAM memory in an EDK project, but I don't knowwhat> I have to do in order to boot from it. I want to store my instructions and > data into it. Does anyone can help me? > > Thank you! > Melissa >SDRAM is VOLATILE memory so you can not boot from it as it does not contain any data. you need some nonvolatile memory for booting, so you can copy this data to the SDRAM and then start execution from SDRAM antti
Reply by ●October 26, 20052005-10-26
Reply by ●October 26, 20052005-10-26
Antti Lukats wrote:>"mvetromille" <mvetromille@gmail.com> schrieb im Newsbeitrag >news:b1bb368c3bf24200aae1c08000ca3267@localhost.talkaboutelectronicequipment.com... > > >>Hello! I instantiated SDRAM memory in an EDK project, but I don't know >> >> >what > > >>I have to do in order to boot from it. I want to store my instructions and >>data into it. Does anyone can help me? >> >> >> > > >You need to design (or instantiate some one else's) SDRAM controller. Working SDRAM is not trivial; it requires a state machine to sequence the controls, not only to access the data, but also to refresh the memory and even to properly initialize the memory before it can be accessed. You can start by reading the data sheet for the particular SDRAM that is on the board. There may be an SDRAM controller in the IP that came with the board, perhaps in one of the example designs. -- --Ray Andraka, P.E. President, the Andraka Consulting Group, Inc. 401/884-7930 Fax 401/884-7950 email ray@andraka.com http://www.andraka.com "They that give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety." -Benjamin Franklin, 1759
Reply by ●October 26, 20052005-10-26
I suppose you use PPC. 1. For real hardware - for booting you use the boot files from edk. They are by default there. After that you can use PPC compiler/debugger to compile and load the code in the memory and execute the program. 2. for simulation - as far as I remember - the C program is "translated" to VHDL code(binary 0 and 1) which is placed in the memory. This is the basic idea - i did this a long time ago and some of the things may be not correct. Look for tutorials (that's what I did ;) )
