nRF51822 64 bitwise arithmetic

[Alev]

Hello. I need to hold 64-bit timer value. I store the 32-bit hardware timer value in one variable (low DWORD) and use an additional uint32_t variable as a an upper part of 64-bit timer value (high DWORD).

So, I have a 64-bit unsigned integer stored in 2 32-bit consecutive variables. All works ok, but it is inconvenient to use this construction in calculations (adding, sub and so on).

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The questions:

1. is nRF51822 supports 64 bit arithmetic?

2. I obtained a strange result when try to use unsigned long long - program is compiled and simple operations (add, sub) is seems to ok, but when I try it in comlex application - it's fault.

3. If nRF51822 don't support a native 64 bit arithmetic, can you recomend some C library to emulate working with those long numbers.

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I use a gcc ARM compliler. Chip revision: nRF51822 QFAAG0.

Thanks.

[pabigot]

Use uint64_t after including <inttypes.h>. If you're formatting it for output, use %llu or PRIu64 or similar macros. long long formatting is not available when using newlib nano.

Be aware that getting an accurate 64-bit timer value taking into account overflow can be tricky, and some details differ depending on whether you're reading from a HFCLK-synchronous TIMER or an LFCLK-synchronous RTC.