From c954fb15de566c2a7251d90b6d2ea6292918e2cd Mon Sep 17 00:00:00 2001
From: Alexandre THOMAZO <alex@thomazo.info>
Date: Sat, 25 Sep 2021 20:35:49 +0200
Subject: [PATCH 1/3] Add support for ESP32

---
 TM1637.cpp | 40 ++++++++++++++++++++++++++--------------
 TM1637.h   |  2 ++
 2 files changed, 28 insertions(+), 14 deletions(-)

diff --git a/TM1637.cpp b/TM1637.cpp
index 83939ad..c67c125 100644
--- a/TM1637.cpp
+++ b/TM1637.cpp
@@ -25,6 +25,10 @@
 #define TM1637_CMD_SET_ADDR        0xC0
 #define TM1637_CMD_DISPLAY         0x88
 
+#if defined(ESP32)
+  #define CLOCK_DELAY 1
+#endif
+
 
 /***************
    ---
@@ -192,14 +196,15 @@ uint8_t TM1637::writeByte(uint8_t data)
   // shift out data 8 bits LSB first
   for (uint8_t i = 8; i > 0; i--)
   {
-    digitalWrite(_clock, LOW);
-    digitalWrite(_data, data & 0x01);
-    digitalWrite(_clock, HIGH);
+    writeSync(_clock, LOW);
+    writeSync(_data, data & 0x01);
+    writeSync(_clock, HIGH);
     data >>= 1;
   }
-  digitalWrite(_clock, LOW);
-  digitalWrite(_data, HIGH);
-  digitalWrite(_clock, HIGH);
+
+  writeSync(_clock, LOW);
+  writeSync(_data, HIGH);
+  writeSync(_clock, HIGH);
 
   // get ACKNOWLEDGE
   pinMode(_data, INPUT);
@@ -216,20 +221,27 @@ uint8_t TM1637::writeByte(uint8_t data)
 
 void TM1637::start()
 {
-  digitalWrite(_clock, HIGH);
-  digitalWrite(_data, HIGH);
-  digitalWrite(_data, LOW);
-  digitalWrite(_clock, LOW);
+  writeSync(_clock, HIGH);
+  writeSync(_data, HIGH);
+  writeSync(_data, LOW);
+  writeSync(_clock, LOW);
 }
 
 
 void TM1637::stop()
 {
-  digitalWrite(_clock, LOW);
-  digitalWrite(_data, LOW);
-  digitalWrite(_clock, HIGH);
-  digitalWrite(_data, HIGH);
+  writeSync(_clock, LOW);
+  writeSync(_data, LOW);
+  writeSync(_clock, HIGH);
+  writeSync(_data, HIGH);
 }
 
+void TM1637::writeSync(uint8_t pin, uint8_t val) {
+  digitalWrite(pin, val);
+
+  #ifdef CLOCK_DELAY
+  delayMicroseconds(CLOCK_DELAY);
+  #endif
+}
 
 // -- END OF FILE --
diff --git a/TM1637.h b/TM1637.h
index ff2a800..b461a09 100644
--- a/TM1637.h
+++ b/TM1637.h
@@ -46,6 +46,8 @@ class TM1637
     uint8_t writeByte(uint8_t data);
     void    start();
     void    stop();
+
+    void writeSync(uint8_t pin, uint8_t val);
 };
 
 // -- END OF FILE --

From 2dadefe263197a432597260a872bbccc2705a0bb Mon Sep 17 00:00:00 2001
From: Alexandre THOMAZO <alex@thomazo.info>
Date: Sun, 26 Sep 2021 14:06:31 +0200
Subject: [PATCH 2/3] Rework ESP32 timing for less waiting

---
 TM1637.cpp | 18 +++++++++++-------
 TM1637.h   |  1 +
 2 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/TM1637.cpp b/TM1637.cpp
index c67c125..129f3f5 100644
--- a/TM1637.cpp
+++ b/TM1637.cpp
@@ -25,10 +25,6 @@
 #define TM1637_CMD_SET_ADDR        0xC0
 #define TM1637_CMD_DISPLAY         0x88
 
-#if defined(ESP32)
-  #define CLOCK_DELAY 1
-#endif
-
 
 /***************
    ---
@@ -236,12 +232,20 @@ void TM1637::stop()
   writeSync(_data, HIGH);
 }
 
-void TM1637::writeSync(uint8_t pin, uint8_t val) {
+void TM1637::writeSync(uint8_t pin, uint8_t val) 
+{
   digitalWrite(pin, val);
 
-  #ifdef CLOCK_DELAY
-  delayMicroseconds(CLOCK_DELAY);
+  #if defined(ESP32)
+    nanoDelay(2);
   #endif
+
+}
+
+void TM1637::nanoDelay(uint16_t n)    // 240 ==> at 240 MHz
+{
+  volatile uint16_t i;
+  for (i = 0; i < n; ++i);
 }
 
 // -- END OF FILE --
diff --git a/TM1637.h b/TM1637.h
index b461a09..11caed2 100644
--- a/TM1637.h
+++ b/TM1637.h
@@ -48,6 +48,7 @@ class TM1637
     void    stop();
 
     void writeSync(uint8_t pin, uint8_t val);
+    void nanoDelay(uint16_t n);
 };
 
 // -- END OF FILE --

From afe0da82a02c2dfbacacf1b65c65095e1d0a1381 Mon Sep 17 00:00:00 2001
From: Alexandre THOMAZO <alex@thomazo.info>
Date: Sun, 26 Sep 2021 15:53:40 +0200
Subject: [PATCH 3/3] Tweaking a little more timing for ESP32

Using new nanoDelay, total time from 133us to 113us
---
 TM1637.cpp | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/TM1637.cpp b/TM1637.cpp
index 129f3f5..48975ce 100644
--- a/TM1637.cpp
+++ b/TM1637.cpp
@@ -242,10 +242,10 @@ void TM1637::writeSync(uint8_t pin, uint8_t val)
 
 }
 
-void TM1637::nanoDelay(uint16_t n)    // 240 ==> at 240 MHz
+void TM1637::nanoDelay(uint16_t n)
 {
-  volatile uint16_t i;
-  for (i = 0; i < n; ++i);
+  volatile uint16_t i = n;
+  while (i--);
 }
 
 // -- END OF FILE --