use the radio RSSI for a source... we may want to shorten this as it takes

3-4 seconds to gather all this...  need to add a blinking light to this
so it's clear that it's still starting..

main.c

@@ -182,6 +182,26 @@ process_line(char *start, char *end)
 	usb_printf("line: %.*s", end - start, start);
 }
 
+/*
+ * Seed the randomness from the radio.  This is not a great
+ * seed, and is hard to gauge how much randomness is really
+ * there.  Assuming about 1 bit per 8 bits looks pretty safe,
+ * so add 256 * 8 / 32 words.
+ */
+static void
+radio_seed_rng(void)
+{
+#if 1
+	uint32_t v;
+	int i;
+
+	for (i = 0; i < 256 * 8 / 32; i++) {
+		v = Radio.Random();
+		strobe_seed_prng((uint8_t *)&v, sizeof v);
+	}
+#endif
+}
+
 int
 main(void)
 {
@@ -191,6 +211,10 @@ main(void)
 
 	BoardInitMcu();
 
+	Radio.Init(&revents);
+
+	radio_seed_rng();
+
 	strobe_rng_save();
 
 	/* turn on LED */
@@ -206,17 +230,8 @@ main(void)
 	usb_printf("\r\n");
 #endif
 
-	Radio.Init(&revents);
-
 	uint32_t v;
 
-	v = Radio.Random();
-	usb_printf("rr: %#x\r\n", v);
-	v = Radio.Random();
-	usb_printf("rr: %#x\r\n", v);
-	v = Radio.Random();
-	usb_printf("rr: %#x\r\n", v);
-
 	usb_printf("gs: %#x\r\n", Radio.GetStatus());
 
 	usb_printf("set modem\r\n");