Hello,
I am facing an issue to use the board RAM available as 4Mb.
My context:
I run the Example XPC567XRKIT PinToggleStationery CW210 but I see something strange with the External RAM from debug memory display.
The content available at 20000000 is exactly the same as 20010000 as any other 64Kb addresses until the available zone defined in EBI.CS[0].OR.R.
It seems that the example does not configure the bus properly on the address/data bus and stays always with the same value.
Have someone experimented something similar or have an idea what I failed ?
Thanks, Hugo
Update on 2016.09.30:
Solved! Go to Solution.
Hi, I have deleted previous communication as I was completely wrong.
XPC567XRKIT PinToggleStationery CW210 example is right and SRAM memory that is installed on EVB memory is CY7C1338 and this is 4Mbit memory i.e. 4-Mbit = 128Kbit×32 = 512kByte!
It means address range is 0x2000_0000 - 0x2007FFFF
What puzzled me was CY7C1338's address lines marked as A_72M, A_36M, A_18M and A_9M that are not internally connected to the die.
These lines are connected only in case user would replace installed SRAM by bigger one.
Sorry for confusions.
Hi, I have deleted previous communication as I was completely wrong.
XPC567XRKIT PinToggleStationery CW210 example is right and SRAM memory that is installed on EVB memory is CY7C1338 and this is 4Mbit memory i.e. 4-Mbit = 128Kbit×32 = 512kByte!
It means address range is 0x2000_0000 - 0x2007FFFF
What puzzled me was CY7C1338's address lines marked as A_72M, A_36M, A_18M and A_9M that are not internally connected to the die.
These lines are connected only in case user would replace installed SRAM by bigger one.
Sorry for confusions.
Thanks David,
I have make an error reading specification of board.
But I have tried the XPC567XRKIT PinToggleStationery CW210 and it contains an error.
If I activate the INIT_EXTERNAL_BUS_INTERFACE_SETUP in MPC55xx_init_debug.c as I ran the program in RAM.
But in the External_SRAM_init of main.c:
/* D_ADD13 - D_ADD15 PCR 260 - 262 */
for (count = 260; count <= 262; count++)
{
SIU.PCR[count].R = 0x0443;
};
I have another question is the function INIT_ExternalBusAndMemory partially doing same task with External_SRAM_init ?
I understand it initialize the MMU to access to external device.
Yes, you are right, thanks. I will correct it.
Regarding second question - at the time I have written first version of the example it INIT_ExternalBusAndMemory either wasn't there or it was incorrectly initialized, I don't remember. Anyway I haven't test it. You can try it letting me now if it works or not.
To MMU - TLB entry for EBI is initialized by boot assist module by default, but you would have to do it in case EBI access from second core, its MMU table needs to be initialized by startup script.