Hello,
I'm using the Embedded Artists LPC1788 development kit and I'm trying to get a very simple RTX application running using the external SDRAM.
Here is what I have so far:
1) A simple RTX application that runs (blinks an LED) with no problem when I use the internal RAM. This same application crashes with a bus fault in "os_sys_init" when I us the external SDRAM.
2) I configure and initialize the external SDRAM before the call to __main (this is working as I can run the same blinking LED using the SDRAM with no RTX.
3) Even if I let me STACK and HEAP remain in the internal RAM but have variables etc.. in the SDRAM I get the bus fault.
4) The bus fault is an IMPRECISERR: Imprecise data bus error
The call stack looks like this when the fault occurs:
HardFault_Handler -> rt_put_rdy_first() -> rt_dispatch() -> rt_task_create() -> SVC_Hanlder...
Does anyone have any suggestions? I see no reason why this should cause a fault.
Thanks.
MAC
NXP sample code tends to look like it was written by students. Their code packages can potentially be used as a complement to the datasheet when figuring something out, but in most situations, the code needs to be rewritten - or not used at all.