From ee3d53b5ae0e7cce9088dd8fd03ae0135af0fea4 Mon Sep 17 00:00:00 2001
From: XDA-Bam <1209896+XDA-Bam@users.noreply.github.com>
Date: Fri, 2 Apr 2021 20:50:17 +0200
Subject: [PATCH] Update display timing defaults for AVR boards

Fixes MarlinFirmware/Marlin#21495
---
 Marlin/src/lcd/dogm/ultralcd_st7920_u8glib_rrd_AVR.cpp | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/Marlin/src/lcd/dogm/ultralcd_st7920_u8glib_rrd_AVR.cpp b/Marlin/src/lcd/dogm/ultralcd_st7920_u8glib_rrd_AVR.cpp
index 1e19bf85e596..24baae221ee5 100644
--- a/Marlin/src/lcd/dogm/ultralcd_st7920_u8glib_rrd_AVR.cpp
+++ b/Marlin/src/lcd/dogm/ultralcd_st7920_u8glib_rrd_AVR.cpp
@@ -34,9 +34,9 @@
 #include "ultralcd_st7920_u8glib_rrd_AVR.h"
 
 #if F_CPU >= 20000000
-  #define CPU_ST7920_DELAY_1 DELAY_NS(0)
+  #define CPU_ST7920_DELAY_1 DELAY_NS(150)
   #define CPU_ST7920_DELAY_2 DELAY_NS(0)
-  #define CPU_ST7920_DELAY_3 DELAY_NS(50)
+  #define CPU_ST7920_DELAY_3 DELAY_NS(150)
 #elif MB(3DRAG, K8200, K8400)
   #define CPU_ST7920_DELAY_1 DELAY_NS(0)
   #define CPU_ST7920_DELAY_2 DELAY_NS(188)
@@ -58,9 +58,9 @@
   #define CPU_ST7920_DELAY_2 DELAY_NS(40)
   #define CPU_ST7920_DELAY_3 DELAY_NS(340)
 #elif F_CPU == 16000000
-  #define CPU_ST7920_DELAY_1 DELAY_NS(0)
+  #define CPU_ST7920_DELAY_1 DELAY_NS(125)
   #define CPU_ST7920_DELAY_2 DELAY_NS(0)
-  #define CPU_ST7920_DELAY_3 DELAY_NS(63)
+  #define CPU_ST7920_DELAY_3 DELAY_NS(125)
 #else
   #error "No valid condition for delays in 'ultralcd_st7920_u8glib_rrd_AVR.h'"
 #endif