// Important: RF *must* be activated on ESP board // https://techtutorialsx.com/2017/12/22/esp32-arduino-random-number-generation/ #ifdef ESP32 # include #endif #ifdef ARDUINO # include #endif static int hydro_random_init(void) { const char ctx[hydro_hash_CONTEXTBYTES] = { 'h', 'y', 'd', 'r', 'o', 'P', 'R', 'G' }; hydro_hash_state st; uint16_t ebits = 0; hydro_hash_init(&st, ctx, NULL); while (ebits < 256) { uint32_t r = esp_random(); delay(10); hydro_hash_update(&st, (const uint32_t *) &r, sizeof r); ebits += 32; } hydro_hash_final(&st, hydro_random_context.state, sizeof hydro_random_context.state); hydro_random_context.counter = ~LOAD64_LE(hydro_random_context.state); return 0; }