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Save 256 bytes of RAM by excluding floating point routine

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dak664 2010-11-21 17:56:36 +00:00
parent b3324c6d23
commit da8ad17c02
1 changed files with 4 additions and 2 deletions
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6
platform/avr-ravenusb/rng.c
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@ -15,8 +15,10 @@
#define RNG_CONF_USE_RADIO_CLOCK ((!RNG_CONF_USE_ADC) && RF230BB)
#endif
#define TEMPORAL_AGITATION() do { static uint8_t agitator; agitator*=97; agitator+=101; _delay_us(agitator>>1); } while (0);
/* delay_us uses floating point which includes (in some avr-gcc's) a 256 byte __clz_tab in the RAM through the .data section. */
/* _delay_loop_1 avoids this, it is 3 CPU cycles per loop, 375ns @ 8MHz */
//#define TEMPORAL_AGITATION() do { static uint8_t agitator; agitator*=97; agitator+=101; _delay_us(agitator>>1); } while (0);
#define TEMPORAL_AGITATION() do { static uint8_t agitator; agitator*=97; agitator+=101; _delay_loop_1(agitator>>1); } while (0);
// -------------------------------------------------------------------------