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SWI handling (LPC2388+Keil)

Posted by Konrad Heksel on March 10, 2009
I successfuly adopted FreeRTOS for the PLC2388 port under Keil uVision. Leds blink :)
Unfortunately, I stuck with futher adopting my current firmware.
Before, I used USB CDC example from Keil. It uses SWI interrupt when writing to endpoint.
"Standard" SWI handler delivered by Keil (SWI.s file) extracts swi argument and also performs context saving.
I have no clue, how to combine this solution with RTOS portYeld() which also uses swi.
I tried to put handler to the SWI routine to the Startup.s file, and in the SWI.s put vPortYieldProcessor and USB_WriteEP to the SWI_Table respectively under SWI_0 and under SWI_1.
This trivial modification does not work. When switching context I don't get correct return address. I tried some modifications to the assembly but without success...
Could you help solving this issue?

Thank you in advance.
Konrad Heksel

P.S. prvSetupTimerInterrupt() function has a possible slight mistake ("FreeRTOS\Source\portable\RVDS\ARM7_LPC21xx\port.c").
In case of LPC23xx there should be substraction of one during init of T0MR0/1 register:
T0MR1 = ulCompareMatch-1;
I'm not sure if this is the case of LPC2129

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