#include <ao_adc_fast.h>
#include <ao_crc.h>
#include <ao_trng_send.h>
+#include <ao_exti.h>
static void
-ao_trng_send(void)
+ao_trng_send_raw(uint16_t *buf)
+{
+ uint16_t i;
+ uint16_t t;
+ uint16_t *rnd = (uint16_t *) ao_adc_ring;
+
+ t = ao_adc_get(AO_USB_IN_SIZE>>1); /* one 16-bit value per two output bytes */
+ for (i = 0; i < AO_USB_IN_SIZE / sizeof (uint16_t); i++) {
+ *buf++ = rnd[t];
+ t = (t + 1) & (AO_ADC_RING_SIZE - 1);
+ }
+}
+
+static void
+ao_trng_send_cooked(uint16_t *buf)
{
- static uint16_t *buffer[2];
- int usb_buf_id;
uint16_t i;
- uint16_t *buf;
uint16_t t;
uint32_t *rnd = (uint32_t *) ao_adc_ring;
+ t = ao_adc_get(AO_USB_IN_SIZE) >> 1; /* one 16-bit value per output byte */
+ for (i = 0; i < AO_USB_IN_SIZE / sizeof (uint16_t); i++) {
+ *buf++ = ao_crc_in_32_out_16(rnd[t]);
+ t = (t + 1) & ((AO_ADC_RING_SIZE>>1) - 1);
+ }
+}
+
+static inline int
+ao_send_raw(void)
+{
+ return !ao_gpio_get(AO_RAW_PORT, AO_RAW_BIT, AO_RAW_PIN);
+}
+
+static void
+ao_trng_send(void)
+{
+ static uint16_t *buffer[2];
+ int usb_buf_id;
+
if (!buffer[0]) {
buffer[0] = ao_usb_alloc();
buffer[1] = ao_usb_alloc();
ao_crc_reset();
+ /* Delay long enough for the HV power supply to stabilize so that the
+ * first bits we read aren't of poor quality
+ */
+ ao_delay(AO_MS_TO_TICKS(250));
+
for (;;) {
- ao_led_on(AO_LED_TRNG_ACTIVE);
- t = ao_adc_get(AO_USB_IN_SIZE) >> 1; /* one 16-bit value per output byte */
- buf = buffer[usb_buf_id];
- for (i = 0; i < AO_USB_IN_SIZE / sizeof (uint16_t); i++) {
- *buf++ = ao_crc_in_32_out_16(rnd[t]);
- t = (t + 1) & ((AO_ADC_RING_SIZE>>1) - 1);
+ if (ao_send_raw()) {
+ ao_led_on(AO_LED_TRNG_RAW);
+ ao_trng_send_raw(buffer[usb_buf_id]);
+ ao_led_off(AO_LED_TRNG_RAW);
+ } else {
+ ao_led_on(AO_LED_TRNG_COOKED);
+ ao_trng_send_cooked(buffer[usb_buf_id]);
+ ao_led_off(AO_LED_TRNG_COOKED);
}
ao_adc_ack(AO_USB_IN_SIZE);
- ao_led_off(AO_LED_TRNG_ACTIVE);
ao_usb_write(buffer[usb_buf_id], AO_USB_IN_SIZE);
usb_buf_id = 1-usb_buf_id;
}
void
ao_trng_send_init(void)
{
+ ao_enable_input(AO_RAW_PORT, AO_RAW_BIT, AO_EXTI_MODE_PULL_UP);
ao_add_task(&ao_trng_send_task, ao_trng_send, "trng_send");
}