Reading CPU registers

luke_ludington — Fri, 28 Jun 2019 17:54:39 GMT

I want to get the value of a register on the CPU, I looked on the spec sheet and found the address (0xE000E014) and I want to name the variable I store the value in "subticks_per_tick"

This is on a TWR-K65F180M running FreeRTOS.

register uint64_t 0xE000E014 asm ("subticks_per_tick");register uint64_t subticks_per_tick asm ("0xE000E014");

first line gets: error: expected identifier or '(' before numeric constant

second line gets: invalid register name for 'subticks_per_tick'

Any other ways of accessing hardware tick would also be super helpful

Re: Reading CPU registers

mjbcswitzerland — Mon, 01 Jul 2019 17:11:00 GMT

Hi Luke

unsigned long ulValue = *(unsigned long *)(0xe000e000 + 0x014);

This is the SYSTICK reload value (24 bits are valid/implemented) so you won't need a 64 bit variable to copy it to.
You should avoid assembler since C coding will do it just as efficiently and is compiler independent.

Regards

Mark

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Kinetis MicrocontrollersのトピックReading CPU registers

Reading CPU registers

Re: Reading CPU registers