From 1679790481a80270e6d79bb7fe069cd71fe46488 Mon Sep 17 00:00:00 2001
From: RetiredWizard <github@retiredwizard.com>
Date: Sat, 11 Feb 2023 20:21:25 -0500
Subject: [PATCH] Tweaked to run without delays on zero w

---
 ports/broadcom/common-hal/neopixel_write/__init__.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/ports/broadcom/common-hal/neopixel_write/__init__.c b/ports/broadcom/common-hal/neopixel_write/__init__.c
index 5629c97425..d685ac53ce 100644
--- a/ports/broadcom/common-hal/neopixel_write/__init__.c
+++ b/ports/broadcom/common-hal/neopixel_write/__init__.c
@@ -97,6 +97,7 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t *digitalinout,
         COMPLETE_MEMORY_READS;
         icnt = 0;
         while ((CM_PWM->CS_b.BUSY == 0) & (icnt++ < 1000)) {
+            COMPLETE_MEMORY_READS;
         }
     }
 
@@ -142,6 +143,7 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t *digitalinout,
             icnt = 0;
             while ((pwm->STA_b.FULL1 == 1) & (icnt++ < 150)) {
                 RUN_BACKGROUND_TASKS;
+                COMPLETE_MEMORY_READS;
             }
             // Dummy value for the first channel.
             pwm->FIF1 = 0x000000;
@@ -149,12 +151,14 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t *digitalinout,
         icnt = 0;
         while ((pwm->STA_b.FULL1 == 1) & (icnt++ < 150)) {
             RUN_BACKGROUND_TASKS;
+            COMPLETE_MEMORY_READS;
         }
         pwm->FIF1 = expanded;
         if (channel == 0) {
             icnt = 0;
             while ((pwm->STA_b.FULL1 == 1) & (icnt++ < 150)) {
                 RUN_BACKGROUND_TASKS;
+                COMPLETE_MEMORY_READS;
             }
             // Dummy value for the second channel.
             pwm->FIF1 = 0x000000;
@@ -164,17 +168,23 @@ void common_hal_neopixel_write(const digitalio_digitalinout_obj_t *digitalinout,
     icnt = 0;
     while ((pwm->STA_b.EMPT1 == 0) & (icnt++ < 2500)) {
         RUN_BACKGROUND_TASKS;
+        COMPLETE_MEMORY_READS;
     }
     // Wait for transmission to start.
     icnt = 0;
     while (((pwm->STA_b.STA1 == 0) & (pwm->STA_b.STA2 == 0)) & (icnt++ < 150)) {
         RUN_BACKGROUND_TASKS;
+        COMPLETE_MEMORY_READS;
     }
     // Wait for transmission to complete.
     icnt = 0;
     while (((pwm->STA_b.STA1 == 1) | (pwm->STA_b.STA2 == 1)) & (icnt++ < 150)) {
         RUN_BACKGROUND_TASKS;
+        COMPLETE_MEMORY_READS;
     }
+    // Shouldn't be anything left in queue but clear it so the clock doesn't crash if there is
+    pwm->CTL = PWM0_CTL_CLRF1_Msk;
+    COMPLETE_MEMORY_READS;
 
     gpio_set_function(digitalinout->pin->number, GPIO_FUNCTION_OUTPUT);