fix merge conflict

11 files changed, 154 insertions, 32 deletions

diff --git a/README.md b/README.md
index 6bc0239b..831baea1 100644
--- a/README.md
+++ b/README.md
@@ -69,7 +69,7 @@ Right now the library is supported on a variety of arduino compatable platforms.
 * Arduino & compatibles - straight up arduino devices, uno, duo, leonardo, mega, nano, etc...
 * Arduino Yún
 * Adafruit Trinket & Gemma - Trinket Pro may be supported, but haven't tested to confirm yet
-* Teensy 2, Teensy++ 2, Teensy 3.0, Teensy 3.1/3.2, Teensy LC, Teensy 3.5, Teensy 3.6, and Teensy 4.0 - arduino compataible from pjrc.com with some extra goodies (note the teensy 3, 3.1, and LC are ARM, not AVR!)
+* Teensy 2, Teensy++ 2, Teensy 3.0, Teensy 3.1/3.2, Teensy LC, Teensy 3.5, Teensy 3.6, and Teensy 4.0 - arduino compatible from pjrc.com with some extra goodies (note the teensy LC, 3.2, 3.5, 3.6, 4.0 are ARM, not AVR!)
 * Arduino Due and the digistump DigiX
 * RFDuino
 * SparkCore
diff --git a/src/led_sysdefs.h b/src/led_sysdefs.h
index d1b1ddab..5db322f8 100644
--- a/src/led_sysdefs.h
+++ b/src/led_sysdefs.h
@@ -24,7 +24,7 @@
 #elif defined(__SAM3X8E__)
 // Include sam/due headers
 #include "platforms/arm/sam/led_sysdefs_arm_sam.h"
-#elif defined(STM32F10X_MD) || defined(__STM32F1__)
+#elif defined(STM32F10X_MD) || defined(__STM32F1__) || defined(STM32F2XX)
 #include "platforms/arm/stm32/led_sysdefs_arm_stm32.h"
 #elif defined(__SAMD21G18A__) || defined(__SAMD21J18A__) || defined(__SAMD21E17A__) || defined(__SAMD21E18A__) 
 #include "platforms/arm/d21/led_sysdefs_arm_d21.h"
diff --git a/src/platforms.h b/src/platforms.h
index 8953ceff..5351e2c1 100644
--- a/src/platforms.h
+++ b/src/platforms.h
@@ -24,7 +24,7 @@
 #elif defined(__SAM3X8E__)
 // Include sam/due headers
 #include "platforms/arm/sam/fastled_arm_sam.h"
-#elif defined(STM32F10X_MD) || defined(__STM32F1__)
+#elif defined(STM32F10X_MD) || defined(__STM32F1__) || defined(STM32F2XX)
 #include "platforms/arm/stm32/fastled_arm_stm32.h"
 #elif defined(__SAMD21G18A__) || defined(__SAMD21J18A__) || defined(__SAMD21E17A__) || defined(__SAMD21E18A__)
 #include "platforms/arm/d21/fastled_arm_d21.h"
diff --git a/src/platforms/arm/d51/fastpin_arm_d51.h b/src/platforms/arm/d51/fastpin_arm_d51.h
index c2a34cc4..6fb5682f 100644
--- a/src/platforms/arm/d51/fastpin_arm_d51.h
+++ b/src/platforms/arm/d51/fastpin_arm_d51.h
@@ -59,7 +59,7 @@ public:
 
 #define _FL_IO(L) _RD32(GPIO ## L)
 
-#define _FL_DEFPIN(PIN, BIT, L) template<> class FastPin<PIN> : public _ARMPIN<PIN, BIT, 1 << BIT, L> {};
+#define _FL_DEFPIN(PIN, BIT, L) template<> class FastPin<PIN> : public _ARMPIN<PIN, BIT, 1ul << BIT, L> {};
 
 // Actual pin definitions
 #if defined(ADAFRUIT_ITSYBITSY_M4_EXPRESS)
@@ -143,10 +143,41 @@ _FL_DEFPIN(PIN_SPI_MISO, 0, 1); _FL_DEFPIN(PIN_SPI_MOSI, 2, 1); _FL_DEFPIN(PIN_S
 #define SPI_DATA PIN_SPI_MOSI
 #define SPI_CLOCK PIN_SPI_SCK
 
-
 #define ARDUNIO_CORE_SPI
 #define HAS_HARDWARE_PIN_SUPPORT 1
 
+#elif defined(ADAFRUIT_MATRIXPORTAL_M4_EXPRESS)
+
+#define MAX_PIN 21
+// 0/1 - SERCOM/UART (Serial1)
+_FL_DEFPIN( 0,  1, 0); _FL_DEFPIN( 1,  0, 0);
+// 2..3 buttons
+_FL_DEFPIN( 2, 22, 1); _FL_DEFPIN( 3, 23, 1);
+// 4 neopixel
+_FL_DEFPIN( 4, 23, 0);
+// SDA/SCL
+_FL_DEFPIN( 5, 31, 1); _FL_DEFPIN( 6, 30, 1);
+// 7..12 RGBRGB pins
+_FL_DEFPIN( 7,  0, 1); _FL_DEFPIN( 8,  1, 1); _FL_DEFPIN( 9,  2, 1); _FL_DEFPIN(10,  3, 1);
+_FL_DEFPIN(11,  4, 1); _FL_DEFPIN(12,  5, 1);
+// 13 LED
+_FL_DEFPIN(13, 14, 0);
+// 14..21  Control pins
+_FL_DEFPIN(14,  6, 1); _FL_DEFPIN(15, 14, 1); _FL_DEFPIN(16, 12, 1); _FL_DEFPIN(17,  7, 1);
+_FL_DEFPIN(18,  8, 1); _FL_DEFPIN(19,  9, 1); _FL_DEFPIN(20, 15, 1); _FL_DEFPIN(21, 13, 1);
+// 22..26 Analog pins
+_FL_DEFPIN(22,  2, 1); _FL_DEFPIN(23,  5, 1); _FL_DEFPIN(24,  4, 1); _FL_DEFPIN(25,  6, 1);
+_FL_DEFPIN(26,  7, 1);
+// 34..36 ESP SPI
+_FL_DEFPIN(34, 16, 0); _FL_DEFPIN(35, 17, 0); _FL_DEFPIN(36, 19, 0); 
+// 48..50 external SPI #2 on sercom 0
+_FL_DEFPIN(48,  5, 0); _FL_DEFPIN(49,  4, 0); _FL_DEFPIN(50,  7, 0); 
+
+#define SPI_DATA 4
+#define SPI_CLOCK 7
+
+#define HAS_HARDWARE_PIN_SUPPORT 1
+
 #endif
 
 
diff --git a/src/platforms/arm/stm32/clockless_arm_stm32.h b/src/platforms/arm/stm32/clockless_arm_stm32.h
index 0ac8a5d4..d87b78c6 100644
--- a/src/platforms/arm/stm32/clockless_arm_stm32.h
+++ b/src/platforms/arm/stm32/clockless_arm_stm32.h
@@ -7,6 +7,13 @@ FASTLED_NAMESPACE_BEGIN
 
 #define FASTLED_HAS_CLOCKLESS 1
 
+#if defined(STM32F2XX)
+// The photon runs faster than the others
+#define ADJ 8
+#else
+#define ADJ 20
+#endif
+
 template <int DATA_PIN, int T1, int T2, int T3, EOrder RGB_ORDER = RGB, int XTRA0 = 0, bool FLIP = false, int WAIT_TIME = 50>
 class ClocklessController : public CPixelLEDController<RGB_ORDER> {
     typedef typename FastPin<DATA_PIN>::port_ptr_t data_ptr_t;
@@ -23,7 +30,7 @@ public:
         mPort = FastPin<DATA_PIN>::port();
     }
 
-  	virtual uint16_t getMaxRefreshRate() const { return 400; }
+    virtual uint16_t getMaxRefreshRate() const { return 400; }
 
 protected:
     virtual void showPixels(PixelController<RGB_ORDER> & pixels) {
@@ -39,28 +46,28 @@ protected:
 
     template<int BITS> __attribute__ ((always_inline)) inline static void writeBits(register uint32_t & next_mark, register data_ptr_t port, register data_t hi, register data_t lo, register uint8_t & b)  {
         for(register uint32_t i = BITS-1; i > 0; --i) {
-            while(_CYCCNT < (T1+T2+T3-20));
+            while(_CYCCNT < (T1+T2+T3-ADJ));
             FastPin<DATA_PIN>::fastset(port, hi);
             _CYCCNT = 4;
             if(b&0x80) {
-                while(_CYCCNT < (T1+T2-20));
+                while(_CYCCNT < (T1+T2-ADJ));
                 FastPin<DATA_PIN>::fastset(port, lo);
             } else {
-                while(_CYCCNT < (T1-10));
+                while(_CYCCNT < (T1-ADJ/2));
                 FastPin<DATA_PIN>::fastset(port, lo);
             }
             b <<= 1;
         }
 
-        while(_CYCCNT < (T1+T2+T3-20));
+        while(_CYCCNT < (T1+T2+T3-ADJ));
         FastPin<DATA_PIN>::fastset(port, hi);
         _CYCCNT = 4;
 
         if(b&0x80) {
-            while(_CYCCNT < (T1+T2-20));
+            while(_CYCCNT < (T1+T2-ADJ));
             FastPin<DATA_PIN>::fastset(port, lo);
         } else {
-            while(_CYCCNT < (T1-10));
+            while(_CYCCNT < (T1-ADJ/2));
             FastPin<DATA_PIN>::fastset(port, lo);
         }
     }
diff --git a/src/platforms/arm/stm32/fastpin_arm_stm32.h b/src/platforms/arm/stm32/fastpin_arm_stm32.h
index bc69912c..548fdc9d 100644
--- a/src/platforms/arm/stm32/fastpin_arm_stm32.h
+++ b/src/platforms/arm/stm32/fastpin_arm_stm32.h
@@ -35,9 +35,14 @@ public:
     inline static void setOutput() { pinMode(PIN, OUTPUT); } // TODO: perform MUX config { _PDDR::r() |= _MASK; }
     inline static void setInput() { pinMode(PIN, INPUT); } // TODO: preform MUX config { _PDDR::r() &= ~_MASK; }
 
+#if defined(STM32F2XX)
+    inline static void hi() __attribute__ ((always_inline)) { _GPIO::r()->BSRRL = _MASK; }
+    inline static void lo() __attribute__ ((always_inline)) { _GPIO::r()->BSRRH = _MASK; }
+#else
     inline static void hi() __attribute__ ((always_inline)) { _GPIO::r()->BSRR = _MASK; }
     inline static void lo() __attribute__ ((always_inline)) { _GPIO::r()->BRR = _MASK; }
     // inline static void lo() __attribute__ ((always_inline)) { _GPIO::r()->BSRR = (_MASK<<16); }
+#endif
     inline static void set(register port_t val) __attribute__ ((always_inline)) { _GPIO::r()->ODR = val; }
 
     inline static void strobe() __attribute__ ((always_inline)) { toggle(); toggle(); }
@@ -51,25 +56,37 @@ public:
     inline static port_t hival() __attribute__ ((always_inline)) { return _GPIO::r()->ODR | _MASK; }
     inline static port_t loval() __attribute__ ((always_inline)) { return _GPIO::r()->ODR & ~_MASK; }
     inline static port_ptr_t port() __attribute__ ((always_inline)) { return &_GPIO::r()->ODR; }
+
+#if defined(STM32F2XX)
+    inline static port_ptr_t sport() __attribute__ ((always_inline)) { return &_GPIO::r()->BSRRL; }
+    inline static port_ptr_t cport() __attribute__ ((always_inline)) { return &_GPIO::r()->BSRRH; }
+#else
     inline static port_ptr_t sport() __attribute__ ((always_inline)) { return &_GPIO::r()->BSRR; }
     inline static port_ptr_t cport() __attribute__ ((always_inline)) { return &_GPIO::r()->BRR; }
+#endif
+
     inline static port_t mask() __attribute__ ((always_inline)) { return _MASK; }
 };
 
-#if defined(STM32F10X_MD)
+
 #define _R(T) struct __gen_struct_ ## T
+#define _FL_DEFPIN(PIN, BIT, L) template<> class FastPin<PIN> : public _ARMPIN<PIN, BIT, 1 << BIT, _R(GPIO ## L)> {};
+
+#if defined(STM32F10X_MD)
 #define _RD32(T) struct __gen_struct_ ## T { static __attribute__((always_inline)) inline volatile GPIO_TypeDef * r() { return T; } };
 #define _FL_IO(L,C) _RD32(GPIO ## L);  _FL_DEFINE_PORT3(L, C, _R(GPIO ## L));
+
 #elif defined(__STM32F1__)
-#define _R(T) struct __gen_struct_ ## T
 #define _RD32(T) struct __gen_struct_ ## T { static __attribute__((always_inline)) inline gpio_reg_map* r() { return T->regs; } };
-#define _FL_IO(L,C) _RD32(GPIO ## L); _FL_DEFINE_PORT3(L, C, _R(GPIO ## L));
+#define _FL_IO(L,C) _RD32(GPIO ## L);  _FL_DEFINE_PORT3(L, C, _R(GPIO ## L));
+
+#elif defined(STM32F2XX)
+#define _RD32(T) struct __gen_struct_ ## T { static __attribute__((always_inline)) inline volatile GPIO_TypeDef * r() { return T; } };
+#define _FL_IO(L,C) _RD32(GPIO ## L);
 #else
 #error "Platform not supported"
 #endif
 
-#define _FL_DEFPIN(PIN, BIT, L) template<> class FastPin<PIN> : public _ARMPIN<PIN, BIT, 1 << BIT, _R(GPIO ## L)> {};
-
 #ifdef GPIOA
 _FL_IO(A,0);
 #endif
@@ -93,7 +110,36 @@ _FL_IO(G,6);
 #endif
 
 // Actual pin definitions
-#if defined(SPARK) // Sparkfun STM32F103 based board
+#if defined(STM32F2XX) // Photon Particle
+
+// https://github.com/focalintent/FastLED-Sparkcore/blob/master/firmware/fastpin_arm_stm32.h
+#define MAX_PIN 20
+_FL_DEFPIN(0, 7, B);
+_FL_DEFPIN(1, 6, B);
+_FL_DEFPIN(2, 5, B);
+_FL_DEFPIN(3, 4, B);
+_FL_DEFPIN(4, 3, B);
+_FL_DEFPIN(5, 15, A);
+_FL_DEFPIN(6, 14, A);
+_FL_DEFPIN(7, 13, A);
+_FL_DEFPIN(10, 5, C);
+_FL_DEFPIN(11, 3, C);
+_FL_DEFPIN(12, 2, C);
+_FL_DEFPIN(13, 5, A);
+_FL_DEFPIN(14, 6, A);
+_FL_DEFPIN(15, 7, A);
+_FL_DEFPIN(16, 4, A);
+_FL_DEFPIN(17, 0, A);
+_FL_DEFPIN(18, 10, A);
+_FL_DEFPIN(19, 9, A);
+_FL_DEFPIN(20, 7, C);
+
+#define SPI_DATA 15
+#define SPI_CLOCK 13
+
+#define HAS_HARDWARE_PIN_SUPPORT
+
+#elif defined(SPARK) // Sparkfun STM32F103 based board
 
 #define MAX_PIN 19
 _FL_DEFPIN(0, 7, B);
@@ -122,9 +168,7 @@ _FL_DEFPIN(19, 2, A);
 
 #define HAS_HARDWARE_PIN_SUPPORT
 
-#endif // SPARK
-
-#if defined(__STM32F1__) // Generic STM32F103 aka "Blue Pill"
+#elif defined(__STM32F1__) // Generic STM32F103 aka "Blue Pill"
 
 #define MAX_PIN 46
 
diff --git a/src/platforms/arm/stm32/led_sysdefs_arm_stm32.h b/src/platforms/arm/stm32/led_sysdefs_arm_stm32.h
index afcf1785..b58779ff 100644
--- a/src/platforms/arm/stm32/led_sysdefs_arm_stm32.h
+++ b/src/platforms/arm/stm32/led_sysdefs_arm_stm32.h
@@ -1,7 +1,7 @@
 #ifndef __INC_LED_SYSDEFS_ARM_SAM_H
 #define __INC_LED_SYSDEFS_ARM_SAM_H
 
-#if defined(STM32F10X_MD)
+#if defined(STM32F10X_MD) || defined(STM32F2XX)
 
 #include <application.h>
 
@@ -55,7 +55,16 @@ typedef volatile       uint8_t RwReg; /**< Read-Write 8-bit register (volatile u
 
 #define FASTLED_NO_PINMAP
 
-#ifndef F_CPU
+#if defined(STM32F2XX)
+#define F_CPU 120000000
+#else
 #define F_CPU 72000000
 #endif
+
+#if defined(STM32F2XX)
+// Photon doesn't provide yield
+#define FASTLED_NEEDS_YIELD
+extern "C" void yield();
 #endif
+
+#endif // defined(STM32F10X_MD) || defined(STM32F2XX)
diff --git a/src/platforms/avr/clockless_trinket.h b/src/platforms/avr/clockless_trinket.h
index 971a5a71..2cfbef0d 100644
--- a/src/platforms/avr/clockless_trinket.h
+++ b/src/platforms/avr/clockless_trinket.h
@@ -172,7 +172,8 @@ protected:
 #define USE_ASM_MACROS
 
 #if defined(__AVR_ATmega4809__)
-#define ASM_VAR_PORT "r" (((PORT_t*)FastPin<DATA_PIN>::port())->OUT)
+// Not used - place holder so existing ASM_VARS macro can remain the same
+#define ASM_VAR_PORT "r" (*FastPin<DATA_PIN>::port())
 #else
 #define ASM_VAR_PORT "M" (FastPin<DATA_PIN>::port() - 0x20)
 #endif
@@ -204,12 +205,24 @@ protected:
 				[O1] "M" (RGB_BYTE1(RGB_ORDER)),		\
 				[O2] "M" (RGB_BYTE2(RGB_ORDER))		\
 				: "cc" /* clobber registers */
-// Note: the code in the else in HI1/LO1 will be turned into an sts (2 cycle, 2 word) opcode
+
+#if defined(__AVR_ATmega4809__)
+
+// 1 cycle, write hi to the port
+#define HI1 do {*FastPin<DATA_PIN>::port()=hi;} while(0);
+// 1 cycle, write lo to the port
+#define LO1 do {*FastPin<DATA_PIN>::port()=lo;} while(0);
+
+#else
+
+// Note: the code in the else in HI1/LO1 will be turned into an sts (2 cycle, 2 word)
 // 1 cycle, write hi to the port
 #define HI1 FASTLED_SLOW_CLOCK_ADJUST if((int)(FastPin<DATA_PIN>::port())-0x20 < 64) { asm __volatile__("out %[PORT], %[hi]" ASM_VARS ); } else { *FastPin<DATA_PIN>::port()=hi; }
 // 1 cycle, write lo to the port
 #define LO1 if((int)(FastPin<DATA_PIN>::port())-0x20 < 64) { asm __volatile__("out %[PORT], %[lo]" ASM_VARS ); } else { *FastPin<DATA_PIN>::port()=lo; }
 
+#endif
+
 // 2 cycles, sbrs on flipping the line to lo if we're pushing out a 0
 #define QLO2(B, N) asm __volatile__("sbrs %[" #B "], " #N ASM_VARS ); LO1;
 // load a byte from ram into the given var with the given offset
diff --git a/src/platforms/avr/fastpin_avr.h b/src/platforms/avr/fastpin_avr.h
index 99a78958..741d3f34 100644
--- a/src/platforms/avr/fastpin_avr.h
+++ b/src/platforms/avr/fastpin_avr.h
@@ -37,6 +37,7 @@ public:
 	inline static port_t hival() __attribute__ ((always_inline)) { return _PORT::r() | _MASK; }
 	inline static port_t loval() __attribute__ ((always_inline)) { return _PORT::r() & ~_MASK; }
 	inline static port_ptr_t port() __attribute__ ((always_inline)) { return &_PORT::r(); }
+
 	inline static port_t mask() __attribute__ ((always_inline)) { return _MASK; }
 };
 
@@ -46,15 +47,25 @@ public:
 /// a custom type for each GPIO register with a single, static, aggressively inlined function that returns that specific GPIO register.  A similar
 /// trick is used a bit further below for the ARM GPIO registers (of which there are far more than on AVR!)
 typedef volatile uint8_t & reg8_t;
+
 #define _R(T) struct __gen_struct_ ## T
 #define _RD8(T) struct __gen_struct_ ## T { static inline reg8_t r() { return T; }};
 
 // Register name equivalent (using flat names)
-#if defined(AVR_ATtinyxy7) || defined(AVR_ATtinyxy6) || defined(AVR_ATtinyxy4) || defined(AVR_ATtinyxy2) || defined(__AVR_ATmega4809__)
+#if defined(AVR_ATtinyxy7) || defined(AVR_ATtinyxy6) || defined(AVR_ATtinyxy4) || defined(AVR_ATtinyxy2)
+
 // ATtiny series 0/1 and ATmega series 0
 #define _FL_IO(L,C) _RD8(PORT ## L ## _DIR); _RD8(PORT ## L ## _OUT); _RD8(PORT ## L ## _IN); _FL_DEFINE_PORT3(L, C, _R(PORT ## L ## _OUT));
 #define _FL_DEFPIN(_PIN, BIT, L) template<> class FastPin<_PIN> : public _AVRPIN<_PIN, 1<<BIT, _R(PORT ## L ## _OUT), _R(PORT ## L ## _DIR), _R(PORT ## L ## _IN)> {};
+
+#elif defined(__AVR_ATmega4809__)
+
+// Leverage VPORTs instead of PORTs for faster access
+#define _FL_IO(L,C) _RD8(VPORT ## L ## _DIR); _RD8(VPORT ## L ## _OUT); _RD8(VPORT ## L ## _IN); _FL_DEFINE_PORT3(L, C, _R(VPORT ## L ## _OUT));
+#define _FL_DEFPIN(_PIN, BIT, L) template<> class FastPin<_PIN> : public _AVRPIN<_PIN, 1<<BIT, _R(VPORT ## L ## _OUT), _R(VPORT ## L ## _DIR), _R(VPORT ## L ## _IN)> {};
+
 #else
+
 // Others
 #define _FL_IO(L,C) _RD8(DDR ## L); _RD8(PORT ## L); _RD8(PIN ## L); _FL_DEFINE_PORT3(L, C, _R(PORT ## L));
 #define _FL_DEFPIN(_PIN, BIT, L) template<> class FastPin<_PIN> : public _AVRPIN<_PIN, 1<<BIT, _R(PORT ## L), _R(DDR ## L), _R(PIN ## L)> {};
@@ -231,11 +242,10 @@ _FL_DEFPIN(12, 1, E); _FL_DEFPIN(13, 2, E); _FL_DEFPIN(14, 3, D); _FL_DEFPIN(15,
 _FL_DEFPIN(16, 1, D); _FL_DEFPIN(17, 0, D); _FL_DEFPIN(18, 2, A); _FL_DEFPIN(19, 3, A);
 _FL_DEFPIN(20, 4, D); _FL_DEFPIN(21, 5, D);
 
-// To confirm for the SPI interfaces
-//#define SPI_DATA 18
-//#define SPI_CLOCK 13
-//#define SPI_SELECT 19
-//#define AVR_HARDWARE_SPI 1
+#define SPI_DATA 11
+#define SPI_CLOCK 13
+#define SPI_SELECT 8
+#define AVR_HARDWARE_SPI 1
 #define HAS_HARDWARE_PIN_SUPPORT 1
 
 //#define SPI_UART0_DATA 1
diff --git a/src/platforms/esp/32/clockless_rmt_esp32.cpp b/src/platforms/esp/32/clockless_rmt_esp32.cpp
index 9fbdab59..42db3415 100644
--- a/src/platforms/esp/32/clockless_rmt_esp32.cpp
+++ b/src/platforms/esp/32/clockless_rmt_esp32.cpp
@@ -328,7 +328,11 @@ void IRAM_ATTR ESP32RMTController::interruptHandler(void *arg)
 
     for (channel = 0; channel < gMaxChannel; channel++) {
         int tx_done_bit = channel * 3;
+        #ifdef CONFIG_IDF_TARGET_ESP32S2
+        int tx_next_bit = channel + 12;
+        #else
         int tx_next_bit = channel + 24;
+        #endif
 
         ESP32RMTController * pController = gOnChannel[channel];
         if (pController != NULL) {
diff --git a/src/platforms/esp/32/clockless_rmt_esp32.h b/src/platforms/esp/32/clockless_rmt_esp32.h
index faa31dc5..2a8555ab 100644
--- a/src/platforms/esp/32/clockless_rmt_esp32.h
+++ b/src/platforms/esp/32/clockless_rmt_esp32.h
@@ -188,10 +188,14 @@ __attribute__ ((always_inline)) inline static uint32_t __clock_cycles() {
 #define FASTLED_RMT_MAX_CONTROLLERS 32
 #endif
 
-// -- Max RMT channel (default to 8)
+// -- Max RMT channel (default to 8 on ESP32 and 4 on ESP32-S2)
 #ifndef FASTLED_RMT_MAX_CHANNELS
+#ifdef CONFIG_IDF_TARGET_ESP32S2
+#define FASTLED_RMT_MAX_CHANNELS 4
+#else
 #define FASTLED_RMT_MAX_CHANNELS 8
 #endif
+#endif
 
 class ESP32RMTController
 {