Merge branch 'master' into circuitpython-nickzoic-716-pulseio-esp8266

34 files changed, 294 insertions, 30 deletions

diff --git a/ports/atmel-samd/background.c b/ports/atmel-samd/background.c
index 92648f42e..4cba7a110 100644
--- a/ports/atmel-samd/background.c
+++ b/ports/atmel-samd/background.c
@@ -26,11 +26,19 @@
 #include "background.h"
 
 #include "audio_dma.h"
+#include "tick.h"
 #include "usb.h"
 #include "usb_mass_storage.h"
 
+volatile uint64_t last_finished_tick = 0;
+
 void run_background_tasks(void) {
     audio_dma_background();
     usb_msc_background();
     usb_cdc_background();
+    last_finished_tick = ticks_ms;
+}
+
+bool background_tasks_ok(void) {
+    return ticks_ms - last_finished_tick < 1000;
 }
diff --git a/ports/atmel-samd/background.h b/ports/atmel-samd/background.h
index f7fb10a1f..e841049a4 100644
--- a/ports/atmel-samd/background.h
+++ b/ports/atmel-samd/background.h
@@ -27,6 +27,9 @@
 #ifndef MICROPY_INCLUDED_ATMEL_SAMD_BACKGROUND_H
 #define MICROPY_INCLUDED_ATMEL_SAMD_BACKGROUND_H
 
+#include <stdbool.h>
+
 void run_background_tasks(void);
+bool background_tasks_ok(void);
 
 #endif  // MICROPY_INCLUDED_ATMEL_SAMD_BACKGROUND_H
diff --git a/ports/atmel-samd/bindings/samd/Clock.c b/ports/atmel-samd/bindings/samd/Clock.c
index 3c87177a4..e09cc0bd8 100644
--- a/ports/atmel-samd/bindings/samd/Clock.c
+++ b/ports/atmel-samd/bindings/samd/Clock.c
@@ -47,15 +47,7 @@
 STATIC void samd_clock_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     samd_clock_obj_t *self = MP_OBJ_TO_PTR(self_in);
 
-    mp_printf(print, "%q.%q.%s(", MP_QSTR_samd, MP_QSTR_clock, self->name);
-    if (clock_get_enabled(self->type, self->index)) {
-        mp_printf(print, "frequency=%u", clock_get_frequency(self->type, self->index));
-        uint32_t calibration = clock_get_calibration(self->type, self->index);
-        if (calibration) {
-            mp_printf(print, ", calibration=%u", calibration);
-        }
-    }
-    mp_printf(print, ")");
+    mp_printf(print, "%q.%q.%q", MP_QSTR_samd, MP_QSTR_clock, self->name);
 }
 
 //|     .. attribute:: enabled
diff --git a/ports/atmel-samd/bindings/samd/Clock.h b/ports/atmel-samd/bindings/samd/Clock.h
index 0d13ae253..ccc8f10d1 100644
--- a/ports/atmel-samd/bindings/samd/Clock.h
+++ b/ports/atmel-samd/bindings/samd/Clock.h
@@ -31,7 +31,7 @@
 
 typedef struct {
     mp_obj_base_t base;
-    const char *name;
+    qstr name;
     uint8_t type;
     uint8_t index;
 } samd_clock_obj_t;
@@ -39,7 +39,7 @@ typedef struct {
 #define CLOCK(_name, _type, _index) \
 const samd_clock_obj_t clock_ ## _name = { \
     { &samd_clock_type }, \
-    .name = #_name, \
+    .name = MP_QSTR_ ## _name, \
     .type = _type, \
     .index = _index, \
 }
@@ -47,7 +47,7 @@ const samd_clock_obj_t clock_ ## _name = { \
 #define CLOCK_SOURCE(_name) \
 const samd_clock_obj_t clock_ ## _name = { \
     { &samd_clock_type }, \
-    .name = #_name, \
+    .name = MP_QSTR_ ## _name, \
     .type = 0, \
     .index = GCLK_SOURCE_ ## _name, \
 }
@@ -55,7 +55,7 @@ const samd_clock_obj_t clock_ ## _name = { \
 #define CLOCK_GCLK(_name) \
 const samd_clock_obj_t clock_ ## _name = { \
     { &samd_clock_type }, \
-    .name = #_name, \
+    .name = MP_QSTR_ ## _name, \
     .type = 1, \
     .index = _name ## _GCLK_ID, \
 }
@@ -63,7 +63,7 @@ const samd_clock_obj_t clock_ ## _name = { \
 #define CLOCK_GCLK_(_name, _extra) \
 const samd_clock_obj_t clock_ ## _name ## _ ## _extra = { \
     { &samd_clock_type }, \
-    .name = #_name "_" #_extra, \
+    .name = MP_QSTR_ ## _name ## _ ## _extra, \
     .type = 1, \
     .index = _name ## _GCLK_ID_ ## _extra, \
 }
diff --git a/ports/atmel-samd/boards/arduino_zero/mpconfigboard.h b/ports/atmel-samd/boards/arduino_zero/mpconfigboard.h
index a32f128f5..1382d4736 100644
--- a/ports/atmel-samd/boards/arduino_zero/mpconfigboard.h
+++ b/ports/atmel-samd/boards/arduino_zero/mpconfigboard.h
@@ -24,3 +24,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h b/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h
index 3d97e2cb1..5077840cb 100644
--- a/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/circuitplayground_express/mpconfigboard.h
@@ -68,3 +68,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PB09)
 #define DEFAULT_UART_BUS_TX (&pin_PB08)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/circuitplayground_express_crickit/mpconfigboard.h b/ports/atmel-samd/boards/circuitplayground_express_crickit/mpconfigboard.h
index 83cc19d9f..638a6646c 100644
--- a/ports/atmel-samd/boards/circuitplayground_express_crickit/mpconfigboard.h
+++ b/ports/atmel-samd/boards/circuitplayground_express_crickit/mpconfigboard.h
@@ -71,3 +71,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PB09)
 #define DEFAULT_UART_BUS_TX (&pin_PB08)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/feather_m0_adalogger/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_adalogger/mpconfigboard.h
index 94caa7d04..c8b5c56ee 100644
--- a/ports/atmel-samd/boards/feather_m0_adalogger/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_adalogger/mpconfigboard.h
@@ -22,3 +22,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/feather_m0_basic/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_basic/mpconfigboard.h
index 34de8e166..dcac9749d 100644
--- a/ports/atmel-samd/boards/feather_m0_basic/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_basic/mpconfigboard.h
@@ -23,3 +23,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h
index bfa8c642a..108d67d9f 100644
--- a/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_express/mpconfigboard.h
@@ -58,3 +58,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/feather_m0_express_crickit/board.c b/ports/atmel-samd/boards/feather_m0_express_crickit/board.c
new file mode 100644
index 000000000..c8e20206a
--- /dev/null
+++ b/ports/atmel-samd/boards/feather_m0_express_crickit/board.c
@@ -0,0 +1,38 @@
+/*
+ * This file is part of the MicroPython project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2017 Scott Shawcroft 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 "boards/board.h"
+
+void board_init(void)
+{
+}
+
+bool board_requests_safe_mode(void) {
+    return false;
+}
+
+void reset_board(void) {
+}
diff --git a/ports/atmel-samd/boards/feather_m0_express_crickit/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_express_crickit/mpconfigboard.h
new file mode 100644
index 000000000..756462013
--- /dev/null
+++ b/ports/atmel-samd/boards/feather_m0_express_crickit/mpconfigboard.h
@@ -0,0 +1,60 @@
+#define MICROPY_HW_BOARD_NAME "Adafruit Feather M0 Express with Crickit libraries"
+#define MICROPY_HW_MCU_NAME "samd21g18"
+
+#define MICROPY_HW_NEOPIXEL (&pin_PA06)
+
+// Clock rates are off: Salae reads 12MHz which is the limit even though we set it to the safer 8MHz.
+#define SPI_FLASH_BAUDRATE  (8000000)
+
+#define SPI_FLASH_MOSI_PIN          PIN_PA08
+#define SPI_FLASH_MISO_PIN          PIN_PA14
+#define SPI_FLASH_SCK_PIN           PIN_PA09
+#define SPI_FLASH_CS_PIN            PIN_PA13
+#define SPI_FLASH_MOSI_PIN_FUNCTION PINMUX_PA08D_SERCOM2_PAD0
+#define SPI_FLASH_MISO_PIN_FUNCTION PINMUX_PA14C_SERCOM2_PAD2
+#define SPI_FLASH_SCK_PIN_FUNCTION  PINMUX_PA09D_SERCOM2_PAD1
+#define SPI_FLASH_SERCOM            SERCOM2
+#define SPI_FLASH_SERCOM_INDEX      2
+#define SPI_FLASH_MOSI_PAD          0
+#define SPI_FLASH_MISO_PAD          2
+#define SPI_FLASH_SCK_PAD           1
+// <o> Transmit Data Pinout
+// <0x0=>PAD[0,1]_DO_SCK
+// <0x1=>PAD[2,3]_DO_SCK
+// <0x2=>PAD[3,1]_DO_SCK
+// <0x3=>PAD[0,3]_DO_SCK
+#define SPI_FLASH_DOPO              0
+#define SPI_FLASH_DIPO              2   // same as MISO pad
+
+// These are pins not to reset.
+#define MICROPY_PORT_A        (PORT_PA06 | PORT_PA08 | PORT_PA09 | PORT_PA13 | PORT_PA14 | PORT_PA24 | PORT_PA25)
+#define MICROPY_PORT_B        ( 0 )
+#define MICROPY_PORT_C        ( 0 )
+
+#include "external_flash/external_flash.h"
+
+// If you change this, then make sure to update the linker scripts as well to
+// make sure you don't overwrite code.
+#define CIRCUITPY_INTERNAL_NVM_SIZE 256
+
+#define BOARD_FLASH_SIZE (0x00040000 - 0x2000 - CIRCUITPY_INTERNAL_NVM_SIZE)
+
+#include "external_flash/devices.h"
+
+#define EXTERNAL_FLASH_DEVICE_COUNT 2
+#define EXTERNAL_FLASH_DEVICES S25FL216K, \
+                               GD25Q16C
+
+#include "external_flash/external_flash.h"
+
+#define BOARD_HAS_CRYSTAL 1
+
+#define DEFAULT_I2C_BUS_SCL (&pin_PA23)
+#define DEFAULT_I2C_BUS_SDA (&pin_PA22)
+
+#define DEFAULT_SPI_BUS_SCK (&pin_PB11)
+#define DEFAULT_SPI_BUS_MOSI (&pin_PB10)
+#define DEFAULT_SPI_BUS_MISO (&pin_PA12)
+
+#define DEFAULT_UART_BUS_RX (&pin_PA11)
+#define DEFAULT_UART_BUS_TX (&pin_PA10)
diff --git a/ports/atmel-samd/boards/feather_m0_express_crickit/mpconfigboard.mk b/ports/atmel-samd/boards/feather_m0_express_crickit/mpconfigboard.mk
new file mode 100644
index 000000000..4096560c2
--- /dev/null
+++ b/ports/atmel-samd/boards/feather_m0_express_crickit/mpconfigboard.mk
@@ -0,0 +1,17 @@
+LD_FILE = boards/samd21x18-bootloader-external-flash.ld
+USB_VID = 0x239A
+USB_PID = 0x8023
+USB_PRODUCT = "Feather M0 Express"
+USB_MANUFACTURER = "Adafruit Industries LLC"
+
+SPI_FLASH_FILESYSTEM = 1
+LONGINT_IMPL = MPZ
+
+CHIP_VARIANT = SAMD21G18A
+CHIP_FAMILY = samd21
+
+# Include these Python libraries in firmware.
+FROZEN_MPY_DIRS += $(TOP)/frozen/Adafruit_CircuitPython_BusDevice
+FROZEN_MPY_DIRS += $(TOP)/frozen/Adafruit_CircuitPython_Motor
+FROZEN_MPY_DIRS += $(TOP)/frozen/Adafruit_CircuitPython_NeoPixel
+FROZEN_MPY_DIRS += $(TOP)/frozen/Adafruit_CircuitPython_seesaw
diff --git a/ports/atmel-samd/boards/feather_m0_express_crickit/pins.c b/ports/atmel-samd/boards/feather_m0_express_crickit/pins.c
new file mode 100644
index 000000000..68666c273
--- /dev/null
+++ b/ports/atmel-samd/boards/feather_m0_express_crickit/pins.c
@@ -0,0 +1,33 @@
+#include "shared-bindings/board/__init__.h"
+
+#include "board_busses.h"
+
+STATIC const mp_rom_map_elem_t board_global_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR_A0), MP_ROM_PTR(&pin_PA02) },
+    { MP_ROM_QSTR(MP_QSTR_A1), MP_ROM_PTR(&pin_PB08) },
+    { MP_ROM_QSTR(MP_QSTR_A2), MP_ROM_PTR(&pin_PB09) },
+    { MP_ROM_QSTR(MP_QSTR_A3), MP_ROM_PTR(&pin_PA04) },
+    { MP_ROM_QSTR(MP_QSTR_A4), MP_ROM_PTR(&pin_PA05) },
+    { MP_ROM_QSTR(MP_QSTR_A5), MP_ROM_PTR(&pin_PB02) },
+    { MP_ROM_QSTR(MP_QSTR_SCK), MP_ROM_PTR(&pin_PB11) },
+    { MP_ROM_QSTR(MP_QSTR_MOSI), MP_ROM_PTR(&pin_PB10) },
+    { MP_ROM_QSTR(MP_QSTR_MISO), MP_ROM_PTR(&pin_PA12) },
+    { MP_ROM_QSTR(MP_QSTR_D0), MP_ROM_PTR(&pin_PA11) },
+    { MP_ROM_QSTR(MP_QSTR_RX), MP_ROM_PTR(&pin_PA11) },
+    { MP_ROM_QSTR(MP_QSTR_D1), MP_ROM_PTR(&pin_PA10) },
+    { MP_ROM_QSTR(MP_QSTR_TX), MP_ROM_PTR(&pin_PA10) },
+    { MP_ROM_QSTR(MP_QSTR_SDA), MP_ROM_PTR(&pin_PA22) },
+    { MP_ROM_QSTR(MP_QSTR_SCL), MP_ROM_PTR(&pin_PA23) },
+    { MP_ROM_QSTR(MP_QSTR_D5), MP_ROM_PTR(&pin_PA15) },
+    { MP_ROM_QSTR(MP_QSTR_D6), MP_ROM_PTR(&pin_PA20) },
+    { MP_ROM_QSTR(MP_QSTR_D9), MP_ROM_PTR(&pin_PA07) },
+    { MP_ROM_QSTR(MP_QSTR_D10), MP_ROM_PTR(&pin_PA18) },
+    { MP_ROM_QSTR(MP_QSTR_D11), MP_ROM_PTR(&pin_PA16) },
+    { MP_ROM_QSTR(MP_QSTR_D12), MP_ROM_PTR(&pin_PA19) },
+    { MP_ROM_QSTR(MP_QSTR_D13), MP_ROM_PTR(&pin_PA17) },
+    { MP_ROM_QSTR(MP_QSTR_NEOPIXEL), MP_ROM_PTR(&pin_PA06) },
+    { MP_ROM_QSTR(MP_QSTR_I2C), MP_ROM_PTR(&board_i2c_obj) },
+    { MP_ROM_QSTR(MP_QSTR_SPI), MP_ROM_PTR(&board_spi_obj) },
+    { MP_ROM_QSTR(MP_QSTR_UART), MP_ROM_PTR(&board_uart_obj) },
+};
+MP_DEFINE_CONST_DICT(board_module_globals, board_global_dict_table);
diff --git a/ports/atmel-samd/boards/feather_m0_rfm69/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_rfm69/mpconfigboard.h
index 4f4ea2ffe..4a530ed29 100644
--- a/ports/atmel-samd/boards/feather_m0_rfm69/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_rfm69/mpconfigboard.h
@@ -23,3 +23,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/feather_m0_rfm9x/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_rfm9x/mpconfigboard.h
index a9d586c2e..3a6f28c12 100644
--- a/ports/atmel-samd/boards/feather_m0_rfm9x/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_rfm9x/mpconfigboard.h
@@ -23,3 +23,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h b/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h
index c8118e48b..a7a2d7de0 100644
--- a/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m0_supersized/mpconfigboard.h
@@ -57,3 +57,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/feather_m4_express/mpconfigboard.h b/ports/atmel-samd/boards/feather_m4_express/mpconfigboard.h
index b5af61ba6..c82395baf 100644
--- a/ports/atmel-samd/boards/feather_m4_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/feather_m4_express/mpconfigboard.h
@@ -1,4 +1,4 @@
-#define MICROPY_HW_BOARD_NAME "Feather M4 Express"
+#define MICROPY_HW_BOARD_NAME "Adafruit Feather M4 Express"
 #define MICROPY_HW_MCU_NAME "samd51j19"
 
 #define CIRCUITPY_MCU_FAMILY samd51
@@ -43,3 +43,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PB17)
 #define DEFAULT_UART_BUS_TX (&pin_PB16)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/gemma_m0/mpconfigboard.h b/ports/atmel-samd/boards/gemma_m0/mpconfigboard.h
index 53e802f17..1ec217096 100644
--- a/ports/atmel-samd/boards/gemma_m0/mpconfigboard.h
+++ b/ports/atmel-samd/boards/gemma_m0/mpconfigboard.h
@@ -40,6 +40,9 @@
 #define IGNORE_PIN_PA20     1
 #define IGNORE_PIN_PA21     1
 #define IGNORE_PIN_PA22     1
+// USB is always used.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
 #define IGNORE_PIN_PA27     1
 #define IGNORE_PIN_PA28     1
 #define IGNORE_PIN_PA30     1
diff --git a/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.h b/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.h
index be59bc5d4..f56f57c46 100644
--- a/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.h
@@ -1,4 +1,4 @@
-#define MICROPY_HW_BOARD_NAME "Adafruit Itsy Bitsy M0 Express"
+#define MICROPY_HW_BOARD_NAME "Adafruit ItsyBitsy M0 Express"
 #define MICROPY_HW_MCU_NAME "samd21g18"
 
 #define CIRCUITPY_BITBANG_APA102
@@ -56,3 +56,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.mk b/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.mk
index 66586b611..9f62ae839 100644
--- a/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.mk
+++ b/ports/atmel-samd/boards/itsybitsy_m0_express/mpconfigboard.mk
@@ -1,7 +1,7 @@
 LD_FILE = boards/samd21x18-bootloader-external-flash-crystalless.ld
 USB_VID = 0x239A
 USB_PID = 0x8012
-USB_PRODUCT = "Itsy Bitsy M0 Express"
+USB_PRODUCT = "ItsyBitsy M0 Express"
 USB_MANUFACTURER = "Adafruit Industries LLC"
 
 SPI_FLASH_FILESYSTEM = 1
diff --git a/ports/atmel-samd/boards/itsybitsy_m4_express/mpconfigboard.h b/ports/atmel-samd/boards/itsybitsy_m4_express/mpconfigboard.h
index faa0d6e75..e47d5390d 100644
--- a/ports/atmel-samd/boards/itsybitsy_m4_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/itsybitsy_m4_express/mpconfigboard.h
@@ -1,4 +1,4 @@
-#define MICROPY_HW_BOARD_NAME "ItsyBitsy M4 Express"
+#define MICROPY_HW_BOARD_NAME "Adafruit ItsyBitsy M4 Express"
 #define MICROPY_HW_MCU_NAME "samd51g19"
 
 #define CIRCUITPY_MCU_FAMILY samd51
@@ -41,3 +41,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA16)
 #define DEFAULT_UART_BUS_TX (&pin_PA17)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h b/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h
index f798c5d36..135d6ae92 100644
--- a/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/metro_m0_express/mpconfigboard.h
@@ -59,3 +59,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA11)
 #define DEFAULT_UART_BUS_TX (&pin_PA10)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h b/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h
index 7aef929f7..050f678dd 100644
--- a/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h
+++ b/ports/atmel-samd/boards/metro_m4_express/mpconfigboard.h
@@ -1,4 +1,4 @@
-#define MICROPY_HW_BOARD_NAME "Metro M4 Express"
+#define MICROPY_HW_BOARD_NAME "Adafruit Metro M4 Express"
 #define MICROPY_HW_MCU_NAME "samd51j19"
 
 #define CIRCUITPY_MCU_FAMILY samd51
@@ -44,3 +44,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA23)
 #define DEFAULT_UART_BUS_TX (&pin_PA22)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/trinket_m0/mpconfigboard.h b/ports/atmel-samd/boards/trinket_m0/mpconfigboard.h
index d561947e3..9036f8e7b 100644
--- a/ports/atmel-samd/boards/trinket_m0/mpconfigboard.h
+++ b/ports/atmel-samd/boards/trinket_m0/mpconfigboard.h
@@ -30,6 +30,9 @@
 #define IGNORE_PIN_PA21     1
 #define IGNORE_PIN_PA22     1
 #define IGNORE_PIN_PA23     1
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
 #define IGNORE_PIN_PA27     1
 #define IGNORE_PIN_PA28     1
 #define IGNORE_PIN_PA30     1
diff --git a/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h b/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h
index 3377d1b7e..8e3fdd7a8 100644
--- a/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h
+++ b/ports/atmel-samd/boards/trinket_m0_haxpress/mpconfigboard.h
@@ -64,3 +64,7 @@
 
 #define DEFAULT_UART_BUS_RX (&pin_PA07)
 #define DEFAULT_UART_BUS_TX (&pin_PA06)
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/boards/ugame10/mpconfigboard.h b/ports/atmel-samd/boards/ugame10/mpconfigboard.h
index 4e5e88569..ed822952d 100644
--- a/ports/atmel-samd/boards/ugame10/mpconfigboard.h
+++ b/ports/atmel-samd/boards/ugame10/mpconfigboard.h
@@ -52,3 +52,7 @@
     { MP_OBJ_NEW_QSTR(MP_QSTR_audioio), (mp_obj_t)&audioio_module }, \
     { MP_OBJ_NEW_QSTR(MP_QSTR_gamepad),(mp_obj_t)&gamepad_module }, \
     { MP_OBJ_NEW_QSTR(MP_QSTR__stage), (mp_obj_t)&stage_module }
+
+// USB is always used internally so skip the pin objects for it.
+#define IGNORE_PIN_PA24     1
+#define IGNORE_PIN_PA25     1
diff --git a/ports/atmel-samd/common-hal/audiobusio/PDMIn.c b/ports/atmel-samd/common-hal/audiobusio/PDMIn.c
index 5502fcd81..f16b17770 100644
--- a/ports/atmel-samd/common-hal/audiobusio/PDMIn.c
+++ b/ports/atmel-samd/common-hal/audiobusio/PDMIn.c
@@ -392,7 +392,18 @@ uint32_t common_hal_audiobusio_pdmin_record_to_buffer(audiobusio_pdmin_obj_t* se
             break;
         }
         // Wait for the next buffer to fill
+        uint32_t wait_counts = 0;
+        #ifdef SAMD21
+          #define MAX_WAIT_COUNTS 1000
+        #endif
+        #ifdef SAMD51
+          #define MAX_WAIT_COUNTS 6000
+        #endif
         while (!event_interrupt_active(event_channel)) {
+            if (wait_counts++ > MAX_WAIT_COUNTS) {
+                // Buffer has stopped filling; DMA may have missed an I2S trigger event.
+                break;
+            }
             #ifdef MICROPY_VM_HOOK_LOOP
                 MICROPY_VM_HOOK_LOOP
             #endif
diff --git a/ports/atmel-samd/common-hal/microcontroller/__init__.c b/ports/atmel-samd/common-hal/microcontroller/__init__.c
index c57b6939c..ad4d81ddd 100644
--- a/ports/atmel-samd/common-hal/microcontroller/__init__.c
+++ b/ports/atmel-samd/common-hal/microcontroller/__init__.c
@@ -40,18 +40,10 @@ void common_hal_mcu_delay_us(uint32_t delay) {
     mp_hal_delay_us(delay);
 }
 
-// Interrupt flags that will be saved and restored during disable/Enable
-// interrupt functions below.
-
-// ASF4's interrupt disable doesn't handle duplicate calls
-volatile uint32_t interrupt_flags;
 volatile uint32_t nesting_count = 0;
 void common_hal_mcu_disable_interrupts(void) {
-    if (nesting_count == 0) {
-        interrupt_flags = __get_PRIMASK();
-        __disable_irq();
-        __DMB();
-    }
+    __disable_irq();
+    __DMB();
     nesting_count++;
 }
 
@@ -66,7 +58,7 @@ void common_hal_mcu_enable_interrupts(void) {
         return;
     }
     __DMB();
-    __set_PRIMASK(interrupt_flags);
+    __enable_irq();
 }
 
 extern uint32_t _ezero;
diff --git a/ports/atmel-samd/common-hal/pulseio/PulseIn.c b/ports/atmel-samd/common-hal/pulseio/PulseIn.c
index 99a60a829..d16bbf9d2 100644
--- a/ports/atmel-samd/common-hal/pulseio/PulseIn.c
+++ b/ports/atmel-samd/common-hal/pulseio/PulseIn.c
@@ -31,6 +31,7 @@
 #include "atmel_start_pins.h"
 #include "hal/include/hal_gpio.h"
 
+#include "background.h"
 #include "mpconfigport.h"
 #include "py/gc.h"
 #include "py/runtime.h"
@@ -60,10 +61,16 @@ void pulsein_interrupt_handler(uint8_t channel) {
     uint32_t current_us;
     uint64_t current_ms;
     current_tick(&current_ms, &current_us);
+
     // current_tick gives us the remaining us until the next tick but we want the number since the
     // last ms.
     current_us = 1000 - current_us;
     pulseio_pulsein_obj_t* self = get_eic_channel_data(channel);
+    if (!background_tasks_ok() || self->errored_too_fast) {
+        self->errored_too_fast = true;
+        common_hal_pulseio_pulsein_pause(self);
+        return;
+    }
     if (self->first_edge) {
         self->first_edge = false;
         pulsein_set_config(self, false);
@@ -118,6 +125,7 @@ void common_hal_pulseio_pulsein_construct(pulseio_pulsein_obj_t* self,
     self->first_edge = true;
     self->last_us = 0;
     self->last_ms = 0;
+    self->errored_too_fast = false;
 
     set_eic_channel_data(pin->extint_channel, (void*) self);
 
@@ -157,6 +165,9 @@ void common_hal_pulseio_pulsein_resume(pulseio_pulsein_obj_t* self,
     // Make sure we're paused.
     common_hal_pulseio_pulsein_pause(self);
 
+    // Reset erroring
+    self->errored_too_fast = false;
+
     // Send the trigger pulse.
     if (trigger_duration > 0) {
         gpio_set_pin_pull_mode(self->pin, GPIO_PULL_OFF);
@@ -207,6 +218,11 @@ uint16_t common_hal_pulseio_pulsein_get_len(pulseio_pulsein_obj_t* self) {
     return self->len;
 }
 
+bool common_hal_pulseio_pulsein_get_paused(pulseio_pulsein_obj_t* self) {
+    uint32_t mask = 1 << self->channel;
+    return (EIC->INTENSET.reg & (mask << EIC_INTENSET_EXTINT_Pos)) == 0;
+}
+
 uint16_t common_hal_pulseio_pulsein_get_item(pulseio_pulsein_obj_t* self,
         int16_t index) {
     common_hal_mcu_disable_interrupts();
diff --git a/ports/atmel-samd/common-hal/pulseio/PulseIn.h b/ports/atmel-samd/common-hal/pulseio/PulseIn.h
index 3d79b50c3..f5326d9e5 100644
--- a/ports/atmel-samd/common-hal/pulseio/PulseIn.h
+++ b/ports/atmel-samd/common-hal/pulseio/PulseIn.h
@@ -43,6 +43,7 @@ typedef struct {
     volatile bool first_edge;
     volatile uint64_t last_ms;
     volatile uint16_t last_us;
+    volatile bool errored_too_fast;
 } pulseio_pulsein_obj_t;
 
 void pulsein_reset(void);
diff --git a/ports/atmel-samd/peripherals/samd21/clocks.c b/ports/atmel-samd/peripherals/samd21/clocks.c
index 51b7ad993..422290e8b 100644
--- a/ports/atmel-samd/peripherals/samd21/clocks.c
+++ b/ports/atmel-samd/peripherals/samd21/clocks.c
@@ -130,6 +130,9 @@ static void init_clock_source_dfll48m_xosc(void) {
                             SYSCTRL_DFLLCTRL_ENABLE;
     while (!SYSCTRL->PCLKSR.bit.DFLLRDY) {}
     while (GCLK->STATUS.bit.SYNCBUSY) {}
+
+    // Wait for the fine lock on the DFLL.
+    while (!SYSCTRL->PCLKSR.bit.DFLLLCKC || !SYSCTRL->PCLKSR.bit.DFLLLCKF) {}
 }
 
 static void init_clock_source_dfll48m_usb(void) {
diff --git a/ports/atmel-samd/tick.c b/ports/atmel-samd/tick.c
index 6cd7c7833..9753a1a0c 100644
--- a/ports/atmel-samd/tick.c
+++ b/ports/atmel-samd/tick.c
@@ -60,6 +60,22 @@ void tick_init() {
     uint32_t ticks_per_ms = common_hal_mcu_processor_get_frequency() / 1000;
     SysTick_Config(ticks_per_ms-1);
     NVIC_EnableIRQ(SysTick_IRQn);
+    // Set all peripheral interrupt priorities to the lowest priority by default.
+    for (uint16_t i = 0; i < PERIPH_COUNT_IRQn; i++) {
+        NVIC_SetPriority(i, (1UL << __NVIC_PRIO_BITS) - 1UL);
+    }
+    // Bump up the systick interrupt.
+    NVIC_SetPriority(SysTick_IRQn, 1);
+    #ifdef SAMD21
+    NVIC_SetPriority(USB_IRQn, 1);
+    #endif
+
+    #ifdef SAMD51
+    NVIC_SetPriority(USB_0_IRQn, 1);
+    NVIC_SetPriority(USB_1_IRQn, 1);
+    NVIC_SetPriority(USB_2_IRQn, 1);
+    NVIC_SetPriority(USB_3_IRQn, 1);
+    #endif
 }
 
 void tick_delay(uint32_t us) {
diff --git a/ports/nrf/common-hal/pulseio/PulseIn.c b/ports/nrf/common-hal/pulseio/PulseIn.c
index aa6bb8665..e759ac3a3 100644
--- a/ports/nrf/common-hal/pulseio/PulseIn.c
+++ b/ports/nrf/common-hal/pulseio/PulseIn.c
@@ -71,6 +71,10 @@ uint16_t common_hal_pulseio_pulsein_get_maxlen(pulseio_pulsein_obj_t* self) {
     return 0xadaf;
 }
 
+bool common_hal_pulseio_pulsein_get_paused(pulseio_pulsein_obj_t* self) {
+    return true;
+}
+
 uint16_t common_hal_pulseio_pulsein_get_len(pulseio_pulsein_obj_t* self) {
     return 0xadaf;
 }