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Hi there,
is there a way to generate random numbers by facilities on the ARM9? I don't want to use the libc rand()/srand() but would rather resort to the processors native RNG, which does exist in the NXP MCU product (http://www.nxp.com/documents/data_sheet/LPC3130_31.pdf), so it might as well be present in the FX3.
If it is, is there an easy way to use it? If not, is there any other recommended way to generate a decent amount of entropy (about 4k at a shot)?
Thanks in advance,
/Markus
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Hi Markus,
We do not have a random generator on the FX3 silicon. The only hardware option is to set up a GPIO timer with a low period (period = range of values to be generated) and sample it to get the random number.
The CyU3PGpioSetComplexConfig function can be used as follows to set up the timer:
CyU3PGpioComplexConfig_t gpioConf = {
CyFalse, CyFalse, CyFalse, CyFalse,
CY_U3P_GPIO_MODE_STATIC, /* The GPIO itself is not to be affected, we just use the timer. */
CY_U3P_GPIO_NO_INTR, /* No interrupts associated with this timer. */
CY_U3P_GPIO_TIMER_HIGH_FREQ, /* Run the GPIO at the high clock frequency selected at GpioInit. */
0, /* Start timer at 0. */
RANDOM_MAX, /* Set the period to the range of the numbers to be generated. */
0 /* The threshold is don't care. */
};
CyU3PGpioSetComplexConfig (0, &gpioConf);
The CyU3PGpioComplexSampleNow function can then be used to get the current timer value to serve as a random number.
Please note that the RANDOM_MAX needs to be set to a low value to be able to get good entropy.
Thanks,
Sai Krishna.
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I think you can also use the api CyU3PGetTime to get the system time. I do some operation on it to get a random number .
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hi
who can tell me how to convert the number of tick from CyU3PGpioComplexSampleNow to time