Search found 73 matches
- Sun Mar 08, 2015 12:27 am
- Forum: MicroPython pyboard
- Topic: sha256 and the cortex M4
- Replies: 3
- Views: 6019
sha256 and the cortex M4
I notice that the uhashlib uses crypto-algorithms/sha256.c to implement the hash. Has anyone looked at the Cortex M4 hash processor (chapter 25 ref manual) which provides a hardware implementation of sha256? Looking at the firmware, there are already HAL routines for the hash and SHA256 (stm32f4xx_h...
- Sat Mar 07, 2015 11:53 am
- Forum: MicroPython pyboard
- Topic: pyb.rng() why 30 bits?
- Replies: 3
- Views: 4841
pyb.rng() why 30 bits?
why does pyb.rng() provide only 30 bits of the 32-bit hardware random number generator? hal rng.c shifts off lower 2 bits HAL_RNG_GetRandomNumber(&RNGHandle) >> 2 This app note on NIST tests of STM32Fxx random number generator doesn't report any problems? http://www.st.com/web/en/resource/technical/...
- Sat Mar 07, 2015 1:03 am
- Forum: MicroPython pyboard
- Topic: Can you get the supply voltage?
- Replies: 21
- Views: 22526
Re: Can you get the supply voltage?
on UNO's and such you can measure the supply voltage with the bandgap with the ADC. the pyboard read_core_vref() is not constructed to do that ... too bad. to see what your supply voltage is, you would want to calculate rawvalue*1.21/4095, the you could see if your battery power is sagging ... of co...