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I have just switched from using the standard USB interface to EZLite Kit (Blackfin) to using JTAG (summit ice). And now I am experiencing problems when I try to write to external memory. I have tried to access external memory by following trials: o Loading parts of the program into external memory. o Using the fill memory function. o Modifying the value trough memory view. o Execute small programs which try to o write to external memory. But all of these trials fail when I use the Summit-Ice (when using USB, it works with no problem). Does anyone know why I experiencing this problem? and is there a answer/solution to my problem? Best Regards Gunnleif Blaasvaer M.Sc.EE student Embedded Systems Aalborg University |
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Accessing external memory when using JTAG interface
Started by ●March 30, 2003
Reply by ●March 31, 20032003-03-31
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On Sun, 30 Mar 2003, Gunnleif wrote: > I have just switched from using the standard USB interface to EZLite > Kit (Blackfin) to using JTAG (summit ice). And now I am experiencing > problems when I try to write to external memory. > > I have tried to access external memory by following trials: > o Loading parts of the program into external memory. > o Using the fill memory function. > o Modifying the value trough memory view. > o Execute small programs which try to o write to external memory. > > But all of these trials fail when I use the Summit-Ice (when using > USB, it works with no problem). > > Does anyone know why I experiencing this problem? and is there a > answer/solution to my problem? Check the manual. On the 21061 EZ-KIT the summit ice can not access external memory either. I have no idea why it can't, it's just a memory access. What you can do is write a subroutine to move data to or from external ram, use the ice to set up the registers, and then pull the external data to an internal buffer where the ice can see it. It doesn't make any sense. But I'm not supprised. Patience, persistence, truth, Dr. mike |
Reply by ●March 31, 20032003-03-31
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--- In , "Gunnleif" <gunnleif@k...> wrote: > I have just switched from using the standard USB interface to EZLite > Kit (Blackfin) to using JTAG (summit ice). And now I am experiencing > problems when I try to write to external memory. > With a little help from Analog's European DSP Support I manage to access the external RAM. Basically you have to initialize SDRAM, before it is possible to access it. They suggested that I should initialized via C code - code is listed below: #include <cdef21535.h> void Init_SDRAM(void) { *pEBIU_SDRRC = 0x074A; *pEBIU_SDBCTL = 0x00000001; *pEBIU_SDGCTL = 0x0091998F; } In order for this to work you have to download latest patch for visualdsp++ compiler version 6.2.7 which is available on analog ftp site. I found out myself, that it was possible to initialize SDRAM through assembler without patching visualdsp... I took a piece of the code from the dma_sdram tutorial which comes with the EZLite Kit - code is listed below: #include <def21535.h> #define SDRAM_0 0x00000000 //SDRAM Bank 0 .SECTION init_sdram; .global _init_sdram; _init_sdram: p0.l = EBIU_SDRRC & 0xffff; // Assign LSBs of p0 to point to SDRAM Refresh Rate Control Register p0.h = EBIU_SDRRC >> 16; // Assign MSBs of p0 to point to SDRAM Refresh Rate Control Register r0 = 0x074A (z); // Assign appropriate value to SDRAM Refresh Rate Control Register (zero extend) W[p0] = r0; // from the calculations in the commented section above SSYNC; p0.l = EBIU_SDBCTL & 0xffff; // Assign LSBs of p0 to point to SDRAM Memory Bank Control Register p0.h = EBIU_SDBCTL>> 16; // Assign MSBs of p0 to point to SDRAM Memory Bank Control Register r0 = 0x0001(z); // assign control data word to r0 [p0] = r0; // write control data word to EBIU_SDBCTl SSYNC; p0.l = EBIU_SDGCTL & 0xffff; // Assign LSBs of p0 to point to SDRAM Memory Global Control Register p0.h = EBIU_SDGCTL >> 16; // Assign MSBs of p0 to point to SDRAM Memory Global Control Register r0.l = 0x998d; // assign LSBs of control data word to r0 r0.h = 0x0091; // assign LSBs of control data word to r0 [p0] = r0; // write control data word to EBIU_SDGCTL SSYNC; RTS; _init_sdram_end: This works just as well. Best Regards Gunnleif Blaasvaer M.Sc.EE student Embedded Systems Aalborg University |
