diff --git a/.github/workflows/githubci.yml b/.github/workflows/githubci.yml
index bfce51b..b132048 100644
--- a/.github/workflows/githubci.yml
+++ b/.github/workflows/githubci.yml
@@ -20,7 +20,7 @@ jobs:
       run: bash ci/actions_install.sh
 
     - name: test platforms
-      run: python3 ci/build_platform.py main_platforms
+      run: python3 ci/build_platform.py main_platforms trinket5v
 
     - name: clang
       run: python3 ci/run-clang-format.py -e "ci/*" -e "bin/*" -r . 
diff --git a/Adafruit_BusIO_Register.cpp b/Adafruit_BusIO_Register.cpp
index 1f88d9e..dee13c2 100644
--- a/Adafruit_BusIO_Register.cpp
+++ b/Adafruit_BusIO_Register.cpp
@@ -1,5 +1,7 @@
 #include <Adafruit_BusIO_Register.h>
 
+#if !defined(SPI_INTERFACES_COUNT) || (defined(SPI_INTERFACES_COUNT) && (SPI_INTERFACES_COUNT > 0))
+
 /*!
  *    @brief  Create a register we access over an I2C Device (which defines the
  * bus and address)
@@ -358,3 +360,6 @@ void Adafruit_BusIO_Register::setAddress(uint16_t address) {
 void Adafruit_BusIO_Register::setAddressWidth(uint16_t address_width) {
   _addrwidth = address_width;
 }
+
+
+#endif // SPI exists
diff --git a/Adafruit_BusIO_Register.h b/Adafruit_BusIO_Register.h
index a55cfaf..ba60370 100644
--- a/Adafruit_BusIO_Register.h
+++ b/Adafruit_BusIO_Register.h
@@ -2,6 +2,8 @@
 #include <Adafruit_SPIDevice.h>
 #include <Arduino.h>
 
+#if !defined(SPI_INTERFACES_COUNT) || (defined(SPI_INTERFACES_COUNT) && (SPI_INTERFACES_COUNT > 0))
+
 #ifndef Adafruit_BusIO_Register_h
 #define Adafruit_BusIO_Register_h
 
@@ -98,3 +100,5 @@ private:
 };
 
 #endif // BusIO_Register_h
+
+#endif // SPI exists
diff --git a/Adafruit_I2CDevice.cpp b/Adafruit_I2CDevice.cpp
index f94b1ee..c964490 100644
--- a/Adafruit_I2CDevice.cpp
+++ b/Adafruit_I2CDevice.cpp
@@ -50,8 +50,14 @@ bool Adafruit_I2CDevice::detected(void) {
   // A basic scanner, see if it ACK's
   _wire->beginTransmission(_addr);
   if (_wire->endTransmission() == 0) {
+#ifdef DEBUG_SERIAL
+    DEBUG_SERIAL.println(F("Detected"));
+#endif
     return true;
   }
+#ifdef DEBUG_SERIAL
+    DEBUG_SERIAL.println(F("Not detected"));
+#endif
   return false;
 }
 
@@ -125,7 +131,8 @@ bool Adafruit_I2CDevice::write(const uint8_t *buffer, size_t len, bool stop,
 #endif
 
 #ifdef DEBUG_SERIAL
-  // DEBUG_SERIAL.print("Stop: "); DEBUG_SERIAL.println(stop);
+  DEBUG_SERIAL.print("Stop: ");
+  DEBUG_SERIAL.println(stop);
 #endif
 
   if (_wire->endTransmission(stop) == 0) {
@@ -160,7 +167,12 @@ bool Adafruit_I2CDevice::read(uint8_t *buffer, size_t len, bool stop) {
     return false;
   }
 
+#if defined(TinyWireM_h)
+  size_t recv = _wire->requestFrom((uint8_t)_addr, (uint8_t)len);
+#else
   size_t recv = _wire->requestFrom((uint8_t)_addr, (uint8_t)len, (uint8_t)stop);
+#endif
+
   if (recv != len) {
     // Not enough data available to fulfill our obligation!
 #ifdef DEBUG_SERIAL
@@ -227,10 +239,11 @@ uint8_t Adafruit_I2CDevice::address(void) { return _addr; }
  *    Not necessarily that the speed was achieved!
  */
 bool Adafruit_I2CDevice::setSpeed(uint32_t desiredclk) {
-#if (ARDUINO >= 157) && !defined(ARDUINO_STM32_FEATHER)
+#if (ARDUINO >= 157) && !defined(ARDUINO_STM32_FEATHER) && !defined(TinyWireM_h)
   _wire->setClock(desiredclk);
   return true;
 #else
+  (void)desiredclk;
   return false;
 #endif
 }
diff --git a/Adafruit_SPIDevice.cpp b/Adafruit_SPIDevice.cpp
index 975e31f..c9c1196 100644
--- a/Adafruit_SPIDevice.cpp
+++ b/Adafruit_SPIDevice.cpp
@@ -1,5 +1,7 @@
-#include <Adafruit_SPIDevice.h>
 #include <Arduino.h>
+#include <Adafruit_SPIDevice.h>
+
+#if !defined(SPI_INTERFACES_COUNT) || (defined(SPI_INTERFACES_COUNT) && (SPI_INTERFACES_COUNT > 0))
 
 //#define DEBUG_SERIAL Serial
 
@@ -437,3 +439,5 @@ bool Adafruit_SPIDevice::write_then_read(uint8_t *write_buffer,
 
   return true;
 }
+
+#endif // SPI exists
diff --git a/Adafruit_SPIDevice.h b/Adafruit_SPIDevice.h
index 87506ae..ee9c228 100644
--- a/Adafruit_SPIDevice.h
+++ b/Adafruit_SPIDevice.h
@@ -1,3 +1,5 @@
+#if !defined(SPI_INTERFACES_COUNT) || (defined(SPI_INTERFACES_COUNT) && (SPI_INTERFACES_COUNT > 0))
+
 #include <SPI.h>
 
 #ifndef Adafruit_SPIDevice_h
@@ -97,3 +99,4 @@ private:
 };
 
 #endif // Adafruit_SPIDevice_h
+#endif // has SPI defined