ULINK: Memory Access Error while using ETM Trace on LPC4300
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I have copied an example from Pack Installer based on LPC4300 and made it compatible for ETM Trace as per the settings but as soon as debug session has been started, I see Cannot access Memory error messages in Command Window:
Cannot access Memory (@ 0x00000050, Read, Acc Size: 4 Byte) Cannot access Memory (@ 0x00000052, Read, Acc Size: 2 Byte) Cannot access Memory (@ 0x00000054, Read, Acc Size: 2 Byte) Cannot access Memory (@ 0x00000056, Read, Acc Size: 2 Byte) Cannot access Memory (@ 0x00000058, Read, Acc Size: 4 Byte)
The examples provided in Pack Installer are not compatible for ETM Trace and reason of this error is non-synchronization between System Clock and Trace Core Clock. To make these examples compatible for ETM Trace, the System Clock has to be reduced.
In your µVision project open system_LPC43xx.c, scroll down to section Configure PLL1 and change the settings as per below:
/* PLL1 output clock: 120MHz, Fcco: 240MHz, N = 1, M = 20, P = 1 */ #define PLL1_NSEL 0 /* Range [0 - 3]: Pre-divider ratio N */ #define PLL1_MSEL 19 /* Range [0 - 255]: Feedback-divider ratio M */ #define PLL1_PSEL 0 /* Range [0 - 3]: Post-divider ratio P */ #define PLL1_BYPASS 0 /* 0: Use PLL, 1: PLL is bypassed */ #define PLL1_DIRECT 0 /* 0: Use PSEL, 1: Don't use PSEL */ #define PLL1_FBSEL 0 /* 0: FCCO is used as PLL feedback */
Last Reviewed: Tuesday, April 4, 2017
of your data.