From a29ec85a6c164927ba1e51851d1f42e2cf154c70 Mon Sep 17 00:00:00 2001
From: Tangent 128 <Tangent128@gmail.com>
Date: Sun, 27 Oct 2019 01:20:30 -0400
Subject: [PATCH] Find workable signal timings

---
 itsybitsy_m0_lights/src/lib.rs | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/itsybitsy_m0_lights/src/lib.rs b/itsybitsy_m0_lights/src/lib.rs
index ccf9365..aa3062a 100644
--- a/itsybitsy_m0_lights/src/lib.rs
+++ b/itsybitsy_m0_lights/src/lib.rs
@@ -42,10 +42,17 @@ pub fn boot() -> NeopixelLights<impl OutputPin<Error = ()>, impl OutputPin<Error
 
 // WS2815 lighting times
 // approx. 20ns per clock cycle;
-const ZERO_HIGH_CYCLES: u32 = 11; // about 220ns
-const ONE_HIGH_CYCLES: u32 = 29; // about 580ns
-const ZERO_LOW_CYCLES: u32 = 29; // about 580ns
-const ONE_LOW_CYCLES: u32 = 11; // about 220ns
+// const ZERO_HIGH_CYCLES: u32 = 11; // about 220ns
+// const ONE_HIGH_CYCLES: u32 = 29; // about 580ns
+// const ZERO_LOW_CYCLES: u32 = 29; // about 580ns
+// const ONE_LOW_CYCLES: u32 = 11; // about 220ns
+
+// experimentally, there is some unknown overhead
+// but these timings appear to work for me:
+const ZERO_HIGH_CYCLES: u32 = 11-8;
+const ONE_HIGH_CYCLES: u32 = 29-8;
+const ZERO_LOW_CYCLES: u32 = 29-8;
+const ONE_LOW_CYCLES: u32 = 11-8;
 const LATCH_CYCLES: u32 = 15000; // about 300us
 
 pub struct NeopixelLights<T: OutputPin, U: OutputPin, V: OutputPin> {