From 31117082f0adec4f01e1851aba701e49f047bdf6 Mon Sep 17 00:00:00 2001
From: Michal Moskal <michal@moskal.me>
Date: Sat, 22 Jun 2019 20:38:56 -0700
Subject: [PATCH] Improve UX of gen-random; add note to readme

---
 README.md      | 1 +
 patcher/web.js | 3 ++-
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index a1c4f25..d4b98f8 100644
--- a/README.md
+++ b/README.md
@@ -98,6 +98,7 @@ The reason to pick numbers at random is to minimize risk of collisions
 in the wild. Do not pick random numbers by banging on keyboard, or by using
 `0xdeadf00d`, `0x42424242` etc. A good way is to use the following
 shell command: `printf "0x%04x%04x\n" $RANDOM $RANDOM`
+Another good way is the link at the bottom of https://microsoft.github.io/uf2/patcher/
 This procedure was unfortunately not used for the SAMD51 and NRF52840 below.
 
 #### Family list
diff --git a/patcher/web.js b/patcher/web.js
index 6cc4689..180fb18 100644
--- a/patcher/web.js
+++ b/patcher/web.js
@@ -5,7 +5,8 @@ function savePatch(ev) {
     localStorage["UF2_PATCH"] = text.value
 }
 
-function genRnd() {
+function genRnd(ev) {
+    ev.preventDefault()
     let vals = new Uint32Array(1)
     window.crypto.getRandomValues(vals)
     document.getElementById("rnd-res").textContent = "Random number: 0x" +