diff --git a/include/SPIPortManager.h b/include/SPIPortManager.h
index 7fb67eff4..07febe5d3 100644
--- a/include/SPIPortManager.h
+++ b/include/SPIPortManager.h
@@ -4,6 +4,23 @@
 #include <array>
 #include <optional>
 #include <string>
+#include <driver/spi_master.h>
+
+/**
+ * SPI# to SPI ID and SPI_HOST mapping
+ *
+ * ESP32-S3
+ * | SPI # | SPI ID | SPI_HOST |
+ * | 0     | 0      | 0        |
+ * | 1     | 1      | 1        |
+ * | 2     | 3      | 2        |
+ *
+ * ESP32
+ * | SPI # | SPI ID | SPI_HOST |
+ * | 0     | 1      | 0        |
+ * | 1     | 2      | 1        |
+ * | 2     | 3      | 2        |
+ */
 
 class SPIPortManagerClass {
 public:
@@ -12,6 +29,10 @@ class SPIPortManagerClass {
     std::optional<uint8_t> allocatePort(std::string const& owner);
     void freePort(std::string const& owner);
 
+    spi_host_device_t SPIhostNum(uint8_t spi_num) { return (spi_host_device_t)(spi_num + _offset_spi_num); }
+
+private:
+
     // the amount of SPIs available on supported ESP32 chips
     #if CONFIG_IDF_TARGET_ESP32 || CONFIG_IDF_TARGET_ESP32S2 || CONFIG_IDF_TARGET_ESP32S3
     static size_t constexpr _num_controllers = 2;
@@ -19,15 +40,13 @@ class SPIPortManagerClass {
     static size_t constexpr _num_controllers = 1;
     #endif
     #if CONFIG_IDF_TARGET_ESP32C3 || CONFIG_IDF_TARGET_ESP32S3
-    static int8_t constexpr _start_spi_num = 0;
-    static int8_t constexpr _offset_spi_num = 1;
+    static int8_t constexpr _start_spi_num = 0; // FSPI=0, HSPI=1
+    static int8_t constexpr _offset_spi_num = 1; // SPI1_HOST=0 but not usable, SPI2_HOST=1 and SPI3_HOST=2, first usable is SPI2_HOST
     #else
-    static int8_t constexpr _start_spi_num = 2;
-    static int8_t constexpr  _offset_spi_num = -1;
+    static int8_t constexpr _start_spi_num = 2; // HSPI=2, VSPI=3
+    static int8_t constexpr  _offset_spi_num = -1; // SPI1_HOST=0 but not usable, SPI2_HOST=1 and SPI3_HOST=2, first usable is SPI2_HOST
     #endif
 
-private:
-
     std::array<std::string, _num_controllers> _ports = { "" };
 };
 
diff --git a/lib/CMT2300a/cmt2300a_hal.c b/lib/CMT2300a/cmt2300a_hal.c
index ed920f785..73f6cab71 100644
--- a/lib/CMT2300a/cmt2300a_hal.c
+++ b/lib/CMT2300a/cmt2300a_hal.c
@@ -26,7 +26,7 @@
  * @name    CMT2300A_InitSpi
  * @desc    Initializes the CMT2300A SPI interface.
  * *********************************************************/
-void CMT2300A_InitSpi(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed)
+void CMT2300A_InitSpi(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed)
 {
     cmt_spi3_init(spi_host, pin_sdio, pin_clk, pin_cs, pin_fcs, spi_speed);
 }
diff --git a/lib/CMT2300a/cmt2300a_hal.h b/lib/CMT2300a/cmt2300a_hal.h
index a84da56bc..150e10f09 100644
--- a/lib/CMT2300a/cmt2300a_hal.h
+++ b/lib/CMT2300a/cmt2300a_hal.h
@@ -23,6 +23,7 @@
 
 #include <stdint.h>
 #include <Arduino.h>
+#include <driver/spi_master.h>
 
 #ifdef __cplusplus
 extern "C" {
@@ -36,7 +37,7 @@ extern "C" {
 #define CMT2300A_GetTickCount() millis()
 /* ************************************************************************ */
 
-void CMT2300A_InitSpi(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed);
+void CMT2300A_InitSpi(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed);
 
 uint8_t CMT2300A_ReadReg(const uint8_t addr);
 void CMT2300A_WriteReg(const uint8_t addr, const uint8_t dat);
diff --git a/lib/CMT2300a/cmt2300wrapper.cpp b/lib/CMT2300a/cmt2300wrapper.cpp
index c95874107..f04bdeea9 100644
--- a/lib/CMT2300a/cmt2300wrapper.cpp
+++ b/lib/CMT2300a/cmt2300wrapper.cpp
@@ -7,7 +7,7 @@
 #include "cmt2300a_params_860.h"
 #include "cmt2300a_params_900.h"
 
-CMT2300A::CMT2300A(const int8_t spi_host, const uint8_t pin_sdio, const uint8_t pin_clk, const uint8_t pin_cs, const uint8_t pin_fcs, const uint32_t spi_speed)
+CMT2300A::CMT2300A(const spi_host_device_t spi_host, const uint8_t pin_sdio, const uint8_t pin_clk, const uint8_t pin_cs, const uint8_t pin_fcs, const uint32_t spi_speed)
 {
     _spi_host = spi_host;
     _pin_sdio = pin_sdio;
diff --git a/lib/CMT2300a/cmt2300wrapper.h b/lib/CMT2300a/cmt2300wrapper.h
index 91e2f69ae..b818d972b 100644
--- a/lib/CMT2300a/cmt2300wrapper.h
+++ b/lib/CMT2300a/cmt2300wrapper.h
@@ -2,6 +2,7 @@
 #pragma once
 
 #include <stdint.h>
+#include <driver/spi_master.h>
 
 #define CMT2300A_ONE_STEP_SIZE 2500 // frequency channel step size for fast frequency hopping operation: One step size is 2.5 kHz.
 #define FH_OFFSET 100 // value * CMT2300A_ONE_STEP_SIZE = channel frequency offset
@@ -18,7 +19,7 @@ enum FrequencyBand_t {
 
 class CMT2300A {
 public:
-    CMT2300A(const int8_t spi_host, const uint8_t pin_sdio, const uint8_t pin_clk, const uint8_t pin_cs, const uint8_t pin_fcs, const uint32_t _spi_speed = CMT_SPI_SPEED);
+    CMT2300A(const spi_host_device_t spi_host, const uint8_t pin_sdio, const uint8_t pin_clk, const uint8_t pin_cs, const uint8_t pin_fcs, const uint32_t _spi_speed = CMT_SPI_SPEED);
 
     bool begin(void);
 
@@ -128,7 +129,7 @@ class CMT2300A {
      */
     bool _init_radio();
 
-    int8_t _spi_host;
+    spi_host_device_t _spi_host;
     int8_t _pin_sdio;
     int8_t _pin_clk;
     int8_t _pin_cs;
diff --git a/lib/CMT2300a/cmt_spi3.c b/lib/CMT2300a/cmt_spi3.c
index 060e7fcd4..fadd8ffde 100644
--- a/lib/CMT2300a/cmt_spi3.c
+++ b/lib/CMT2300a/cmt_spi3.c
@@ -1,6 +1,5 @@
 #include "cmt_spi3.h"
 #include <Arduino.h>
-#include <driver/spi_master.h>
 #include <esp_rom_gpio.h> // for esp_rom_gpio_connect_out_signal
 
 SemaphoreHandle_t paramLock = NULL;
@@ -16,7 +15,7 @@ SemaphoreHandle_t paramLock = NULL;
 
 spi_device_handle_t spi_reg, spi_fifo;
 
-void cmt_spi3_init(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed)
+void cmt_spi3_init(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed)
 {
     paramLock = xSemaphoreCreateMutex();
 
diff --git a/lib/CMT2300a/cmt_spi3.h b/lib/CMT2300a/cmt_spi3.h
index f30a68616..5cce47db7 100644
--- a/lib/CMT2300a/cmt_spi3.h
+++ b/lib/CMT2300a/cmt_spi3.h
@@ -2,8 +2,9 @@
 #define __CMT_SPI3_H
 
 #include <stdint.h>
+#include <driver/spi_master.h>
 
-void cmt_spi3_init(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed);
+void cmt_spi3_init(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const uint32_t spi_speed);
 
 void cmt_spi3_write(const uint8_t addr, const uint8_t dat);
 uint8_t cmt_spi3_read(const uint8_t addr);
diff --git a/lib/Hoymiles/src/Hoymiles.cpp b/lib/Hoymiles/src/Hoymiles.cpp
index 28ef23e07..5caa320b7 100644
--- a/lib/Hoymiles/src/Hoymiles.cpp
+++ b/lib/Hoymiles/src/Hoymiles.cpp
@@ -36,7 +36,7 @@ void HoymilesClass::initNRF(SPIClass* initialisedSpiBus, const uint8_t pinCE, co
 }
 
 #ifdef USE_RADIO_CMT
-void HoymilesClass::initCMT(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3)
+void HoymilesClass::initCMT(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3)
 {
     _radioCmt->init(spi_host, pin_sdio, pin_clk, pin_cs, pin_fcs, pin_gpio2, pin_gpio3);
 }
diff --git a/lib/Hoymiles/src/Hoymiles.h b/lib/Hoymiles/src/Hoymiles.h
index 349bd703a..dfd13cc66 100644
--- a/lib/Hoymiles/src/Hoymiles.h
+++ b/lib/Hoymiles/src/Hoymiles.h
@@ -20,7 +20,7 @@ class HoymilesClass {
     void init();
     void initNRF(SPIClass* initialisedSpiBus, const uint8_t pinCE, const uint8_t pinIRQ);
 #ifdef USE_RADIO_CMT
-    void initCMT(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3);
+    void initCMT(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3);
 #endif
     void loop();
 
diff --git a/lib/Hoymiles/src/HoymilesRadio_CMT.cpp b/lib/Hoymiles/src/HoymilesRadio_CMT.cpp
index 6a8dc5887..55d5d96e5 100644
--- a/lib/Hoymiles/src/HoymilesRadio_CMT.cpp
+++ b/lib/Hoymiles/src/HoymilesRadio_CMT.cpp
@@ -85,7 +85,7 @@ bool HoymilesRadio_CMT::cmtSwitchDtuFreq(const uint32_t to_frequency)
     return true;
 }
 
-void HoymilesRadio_CMT::init(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3)
+void HoymilesRadio_CMT::init(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3)
 {
     _dtuSerial.u64 = 0;
 
diff --git a/lib/Hoymiles/src/HoymilesRadio_CMT.h b/lib/Hoymiles/src/HoymilesRadio_CMT.h
index 984e083dc..b6c00cc8d 100644
--- a/lib/Hoymiles/src/HoymilesRadio_CMT.h
+++ b/lib/Hoymiles/src/HoymilesRadio_CMT.h
@@ -5,6 +5,7 @@
 #include "commands/CommandAbstract.h"
 #include "types.h"
 #include <Arduino.h>
+#include <driver/spi_master.h>
 #include <cmt2300wrapper.h>
 #include <memory>
 #include <queue>
@@ -41,7 +42,7 @@ struct CountryFrequencyList_t {
 
 class HoymilesRadio_CMT : public HoymilesRadio {
 public:
-    void init(const int8_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3);
+    void init(const spi_host_device_t spi_host, const int8_t pin_sdio, const int8_t pin_clk, const int8_t pin_cs, const int8_t pin_fcs, const int8_t pin_gpio2, const int8_t pin_gpio3);
     void loop();
     void setPALevel(const int8_t paLevel);
     void setInverterTargetFrequency(const uint32_t frequency);
diff --git a/src/InverterSettings.cpp b/src/InverterSettings.cpp
index 889e9db7b..46b685acf 100644
--- a/src/InverterSettings.cpp
+++ b/src/InverterSettings.cpp
@@ -69,7 +69,7 @@ void InverterSettingsClass::init(Scheduler& scheduler)
         if (PinMapping.isValidCmt2300Config()) {
             auto oSPInum = SPIPortManager.allocatePort("CMT2300A");
             if (oSPInum) {
-                Hoymiles.initCMT(*oSPInum + SPIPortManagerClass::_offset_spi_num, pin.cmt_sdio, pin.cmt_clk, pin.cmt_cs, pin.cmt_fcs, pin.cmt_gpio2, pin.cmt_gpio3);
+                Hoymiles.initCMT(SPIPortManager.SPIhostNum(*oSPInum), pin.cmt_sdio, pin.cmt_clk, pin.cmt_cs, pin.cmt_fcs, pin.cmt_gpio2, pin.cmt_gpio3);
                 MessageOutput.println("  Setting CMT target frequency... ");
                 Hoymiles.getRadioCmt()->setInverterTargetFrequency(config.Dtu.Cmt.Frequency);
             }