diff --git a/ports/stm32f4/common-hal/busio/I2C.c b/ports/stm32f4/common-hal/busio/I2C.c
index c2f5dbe0a2..d2292845ea 100644
--- a/ports/stm32f4/common-hal/busio/I2C.c
+++ b/ports/stm32f4/common-hal/busio/I2C.c
@@ -36,6 +36,7 @@
 #include "common-hal/microcontroller/Pin.h"
 
 STATIC bool reserved_i2c[3];
+STATIC bool never_reset[3];
 
 void i2c_reset(void) {
     //Note: I2Cs are also forcibly reset in construct, due to silicon error
@@ -48,11 +49,24 @@ void i2c_reset(void) {
         __HAL_RCC_I2C2_CLK_DISABLE(); 
     #endif
     #ifdef I2C3
-        reserved_i2c[3] = false;
+        reserved_i2c[2] = false;
         __HAL_RCC_I2C3_CLK_DISABLE(); 
     #endif
 }
 
+void common_hal_busio_i2c_never_reset(busio_i2c_obj_t *self) {
+    for (size_t i = 0 ; i < MP_ARRAY_SIZE(mcu_i2c_banks); i++) {
+        if (self->handle.Instance == mcu_i2c_banks[i]) {
+            never_reset[i] = true;
+
+            never_reset_pin_number(self->scl->pin->port, self->scl->pin->number);
+            never_reset_pin_number(self->sda->pin->port, self->scl->pin->number);
+            break;
+        }
+    }
+}
+
+
 void common_hal_busio_i2c_construct(busio_i2c_obj_t *self,
         const mcu_pin_obj_t* scl, const mcu_pin_obj_t* sda, uint32_t frequency, uint32_t timeout) {
 
@@ -166,19 +180,22 @@ void common_hal_busio_i2c_deinit(busio_i2c_obj_t *self) {
     }
     #ifdef I2C1
     if(self->handle.Instance==I2C1) {
-        reserved_i2c[0] = 0;
+        never_reset[0] = false;
+        reserved_i2c[0] = false;
         __HAL_RCC_I2C1_CLK_DISABLE(); 
     }
     #endif
     #ifdef I2C2
     if(self->handle.Instance==I2C2) {
-        reserved_i2c[1] = 0;
+        never_reset[1] = false;
+        reserved_i2c[1] = false;
         __HAL_RCC_I2C2_CLK_DISABLE(); 
     }
     #endif
     #ifdef I2C3
     if(self->handle.Instance==I2C3) {
-        reserved_i2c[3] = 0;
+        never_reset[2] = false;
+        reserved_i2c[2] = false;
         __HAL_RCC_I2C3_CLK_DISABLE(); 
     }
     #endif
diff --git a/ports/stm32f4/common-hal/busio/SPI.c b/ports/stm32f4/common-hal/busio/SPI.c
index b5517f470f..32089887f9 100644
--- a/ports/stm32f4/common-hal/busio/SPI.c
+++ b/ports/stm32f4/common-hal/busio/SPI.c
@@ -165,7 +165,7 @@ void common_hal_busio_spi_construct(busio_spi_obj_t *self,
     self->baudrate = (get_busclock(SPIx)/16);
     self->prescaler = 16;
     self->polarity = 0;
-    self->phase = 1;
+    self->phase = 0;
     self->bits = 8;
 
     claim_pin(sck);
@@ -191,7 +191,8 @@ bool common_hal_busio_spi_deinited(busio_spi_obj_t *self) {
 
 void common_hal_busio_spi_deinit(busio_spi_obj_t *self) {
     spi_clock_disable(1<<(self->sck->spi_index - 1));
-    reserved_spi[self->sck->spi_index - 1] = true;
+    reserved_spi[self->sck->spi_index - 1] = false;
+    never_reset_spi[self->sck->spi_index - 1] = false;
 
     reset_pin_number(self->sck->pin->port,self->sck->pin->number);
     reset_pin_number(self->mosi->pin->port,self->mosi->pin->number);
diff --git a/ports/stm32f4/common-hal/displayio/ParallelBus.c b/ports/stm32f4/common-hal/displayio/ParallelBus.c
new file mode 100644
index 0000000000..1b808ec025
--- /dev/null
+++ b/ports/stm32f4/common-hal/displayio/ParallelBus.c
@@ -0,0 +1,68 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Lucian Copeland for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "shared-bindings/displayio/ParallelBus.h"
+
+#include <stdint.h>
+
+#include "common-hal/microcontroller/Pin.h"
+#include "py/runtime.h"
+#include "shared-bindings/digitalio/DigitalInOut.h"
+#include "shared-bindings/microcontroller/__init__.h"
+
+#include "tick.h"
+
+void common_hal_displayio_parallelbus_construct(displayio_parallelbus_obj_t* self,
+    const mcu_pin_obj_t* data0, const mcu_pin_obj_t* command, const mcu_pin_obj_t* chip_select,
+    const mcu_pin_obj_t* write, const mcu_pin_obj_t* read, const mcu_pin_obj_t* reset) {
+
+    mp_raise_NotImplementedError(translate("ParallelBus not yet supported"));
+}
+
+void common_hal_displayio_parallelbus_deinit(displayio_parallelbus_obj_t* self) {
+
+}
+
+bool common_hal_displayio_parallelbus_reset(mp_obj_t obj) {
+	return false;
+}
+
+bool common_hal_displayio_parallelbus_bus_free(mp_obj_t obj) {
+    return false;
+}
+
+bool common_hal_displayio_parallelbus_begin_transaction(mp_obj_t obj) {
+
+    return false;
+}
+
+void common_hal_displayio_parallelbus_send(mp_obj_t obj, display_byte_type_t byte_type, display_chip_select_behavior_t chip_select, uint8_t *data, uint32_t data_length) {
+
+}
+
+void common_hal_displayio_parallelbus_end_transaction(mp_obj_t obj) {
+
+}
diff --git a/ports/stm32f4/common-hal/displayio/ParallelBus.h b/ports/stm32f4/common-hal/displayio/ParallelBus.h
new file mode 100644
index 0000000000..85d100715e
--- /dev/null
+++ b/ports/stm32f4/common-hal/displayio/ParallelBus.h
@@ -0,0 +1,36 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2019 Lucian Copeland for Adafruit Industries
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef MICROPY_INCLUDED_STM32F4_COMMON_HAL_DISPLAYIO_PARALLELBUS_H
+#define MICROPY_INCLUDED_STM32F4_COMMON_HAL_DISPLAYIO_PARALLELBUS_H
+
+#include "common-hal/digitalio/DigitalInOut.h"
+
+typedef struct {
+    mp_obj_base_t base;
+} displayio_parallelbus_obj_t;
+
+#endif // MICROPY_INCLUDED_STM32F4_COMMON_HAL_DISPLAYIO_PARALLELBUS_H
diff --git a/ports/stm32f4/mpconfigport.mk b/ports/stm32f4/mpconfigport.mk
index 3ae0daaa08..88636a9d89 100644
--- a/ports/stm32f4/mpconfigport.mk
+++ b/ports/stm32f4/mpconfigport.mk
@@ -65,6 +65,9 @@ ifndef CIRCUITPY_NEOPIXEL_WRITE
 CIRCUITPY_NEOPIXEL_WRITE = 1
 endif
 
+ifndef
+CIRCUITPY_DISPLAYIO = 1
+endif
 
 #ifeq ($(MCU_SUB_VARIANT), stm32f412zx)
 #endif
diff --git a/shared-bindings/_bleio/Connection.c b/shared-bindings/_bleio/Connection.c
index da2fbff287..e1e458c226 100644
--- a/shared-bindings/_bleio/Connection.c
+++ b/shared-bindings/_bleio/Connection.c
@@ -80,14 +80,12 @@ STATIC void ensure_connected(bleio_connection_obj_t *self) {
 //|
 //|   .. method:: disconnect()
 //|
-//|     Disconnects from the remote peripheral.
+//|     Disconnects from the remote peripheral. Does nothing if already disconnected.
 //|
 STATIC mp_obj_t bleio_connection_disconnect(mp_obj_t self_in) {
     bleio_connection_obj_t *self = MP_OBJ_TO_PTR(self_in);
-    ensure_connected(self);
-
+    // common_hal_bleio_connection_disconnect() does nothing if already disconnected.
     common_hal_bleio_connection_disconnect(self->connection);
-
     return mp_const_none;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(bleio_connection_disconnect_obj, bleio_connection_disconnect);
diff --git a/shared-module/displayio/FourWire.c b/shared-module/displayio/FourWire.c
index 92d4507dde..256c29642d 100644
--- a/shared-module/displayio/FourWire.c
+++ b/shared-module/displayio/FourWire.c
@@ -49,8 +49,8 @@ void common_hal_displayio_fourwire_construct(displayio_fourwire_obj_t* self,
     gc_never_free(self->bus);
 
     self->frequency = baudrate;
-    self->polarity = common_hal_busio_spi_get_polarity(spi);
-    self->phase = common_hal_busio_spi_get_phase(spi);
+    self->polarity = 0;
+    self->phase = 0;
 
     common_hal_digitalio_digitalinout_construct(&self->command, command);
     common_hal_digitalio_digitalinout_switch_to_output(&self->command, true, DRIVE_MODE_PUSH_PULL);