From f6e9c7688d673b2b715f2e47acceb345ce444c8a Mon Sep 17 00:00:00 2001
From: Chuck <chuck@example.com>
Date: Mon, 18 May 2026 16:27:21 -0400
Subject: [PATCH] =?UTF-8?q?fix(pi5):=20correct=20gpio=5Fslowdown=20guidanc?=
 =?UTF-8?q?e=20=E2=80=94=20Pi=205=20PIO=20default=20is=201,=20not=204-5?=
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The upstream library defaults gpio_slowdown to 1 for Pi 5 (IsPi4() ? 2 : 1).
In PIO mode the value is a pixel-clock divisor, so 4-5 was unnecessarily
conservative advice. Updated help text and error log to reflect the actual
range (1-3 typical for Pi 5 PIO; inverted effect in RIO mode).

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
---
 src/display_manager.py                           | 2 +-
 web_interface/templates/v3/partials/display.html | 4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/display_manager.py b/src/display_manager.py
index fddf73fe..c296bc49 100644
--- a/src/display_manager.py
+++ b/src/display_manager.py
@@ -170,7 +170,7 @@ class DisplayManager:
                 f"Matrix initialization failed — running in fallback/simulation mode "
                 f"(size {fallback_width}x{fallback_height}). Error: {e}. "
                 "On Raspberry Pi 5: ensure rpi-rgb-led-matrix was built from the latest "
-                "submodule (re-run first_time_install.sh) and that gpio_slowdown is 4 or higher."
+                "submodule (re-run first_time_install.sh). gpio_slowdown of 2–3 is typical for Pi 5 PIO mode."
             )
             # Do not raise here; allow fallback mode so web preview and non-hardware environments work
 
diff --git a/web_interface/templates/v3/partials/display.html b/web_interface/templates/v3/partials/display.html
index ac6264b9..686c9f4a 100644
--- a/web_interface/templates/v3/partials/display.html
+++ b/web_interface/templates/v3/partials/display.html
@@ -18,7 +18,7 @@
         <p class="text-sm text-yellow-700 mt-2">
             On Raspberry Pi 5: ensure the library was rebuilt from the latest submodule
             (<code class="bg-yellow-100 px-1 rounded">first_time_install.sh</code>)
-            and set <strong>GPIO Slowdown to 4 or higher</strong> below.
+            and try adjusting <strong>GPIO Slowdown</strong> (start at 3, reduce if the display looks dim or choppy).
             Check the <a href="/v3/logs" class="underline font-medium">Logs tab</a> for the full error.
         </p>
     </div>
@@ -178,7 +178,7 @@
                            min="0"
                            max="10"
                            class="form-control">
-                    <p class="mt-1 text-sm text-gray-600">Pi 3: 3 &middot; Pi 4: 4 &middot; Pi 5: 4&ndash;5 (in RIO mode, lower values may work better)</p>
+                    <p class="mt-1 text-sm text-gray-600">Pi 3: 1&ndash;2 &middot; Pi 4: 2&ndash;4 &middot; Pi 5 PIO: 1&ndash;3. Increase if display shows garbage; in RIO mode higher values may improve performance.</p>
                 </div>
 
                 <div class="form-group">