nrf: Replace custom-HAL with nrfx-HAL

Summarized this squashed PR replaces the hal/ folder in the port. This has been replaced the official
HAL layer from Nordic Semiconductor; https://github.com/NordicSemiconductor/nrfx.

A Git submodule has been added under lib/nrfx, for the nrfx dependency.

The drivers / modules has been updated to use this new HAL layer; nrfx at v1.0.0.

Also, header files and system files for nrf51/nrf52x chip variants has been deleted from the device/ folder, only keeping back the startup files written in C. All other files are now fetched from nrfx.

3 new header files in the ports/nrf/ folder has been added to configure nrfx (nrfx_config.h), logging (nrfx_log.h) and glue nrfx together with the drivers and modules from micropython (nrfx_glue.h).

The PR has been a joint effort from @aykevl (Ayke van Laethem) and @glennrub.

For reference, the commit log will be kept to get an overview of the changes done:

* ports/nrf: Initial commit for moving hal to Nordic Semiconductor BSD-3 licensed nrfx-hal.

* ports/nrf: Adding nrfx, Nordic Semiconductor BSD-3 hal layer, as git submodule checked out at lib/nrfx.

* ports/nrf/modules/machine/uart: Fixing bug which set hwfc to parity excluded, always resulting in no flow control, hence corrupted output. Also adding an extra loop on uart_tx_char to prevent any tx when any ongoing tx is in progress.

* ports/nrf/i2c: Moving I2C over to nrfx driver.

* ports/nrf/modules/machine/i2c: Alignment. Renaming print function param 'o' to 'self_in'

* ports/nrf/spi: Updating SPI machine module to use nrfx drivers.

* ports/nrf: Renaming modules/machine/rtc.c/.h to rtcounter.c/.h to not confuse the peripheral with Real-Time Clock:

* ports/nrf: Updating various files after renaming machine module RTC to RTCounter.

* ports/nrf: Renaming RTC to RTCounter in modmachine globals dict table. Also updating object type name to reflect new module name.

* ports/nrf: Fixing leftovers after renaming rtc to rtcounter.

* ports/nrf: Early untested adoption of nrfx_rtc in RTCounter. Untested.

* nrf/modules/machine/i2c: Improve keyword argument handling

* ports/nrf/modules/temp: Updating Temp machine module to use nrfx defined hal nrf_temp.h. Moving logic of BLE stack awareness to machine module.

* ports/nrf/boards/pca10040: Enable machine Temp module.

* nrf/modules/machine/rtcounter: Remove magic constants.

* ports/nrf: Adding base support for nrfx module logging. Adding option to disable logging of UART as it might log its own setup over UART while the peripheral is not yet set up. Logging of UART could make sense if other transport of log is used.

* ports/nrf: updating nrfx_log.h with more correct parenthisis on macro grouping.

* ports/nrf: Updating nrfx logging with configuration to disable logging of UART module. The pattern can be used to turn off other modules as well. However, for now UART is the only module locking itself by logging before the peripheral is configured. Logging is turned off by default, can be enabled in nrfx_config.h by setting NRFX_LOG_ENABLED=1.

* ports/nrf/modules/random: Updating modrandom to use nrfx hal for rng. Not using nrfx-driver for this peripheral as its blocking mode would do the trick on RNG. Moving softdevice aware code from legacy hal to modrandom.c.

* nrf: Enable Peripheral Resource Sharing.

This enables TWI and SPI to be enabled at the same time.

* nrf/Makefile: Define MCU sub variant (e.g. NRF51822/NRF51422)

* nrf: Port TIMER peripheral to nrfx HAL.

* nrf/modules/machine/uart: Optimize UART module

For a nRF51, this results in a size reduction of:
.text: -68 bytes
.data: -56 bytes

* nrf/modules/machine/uart: Don't use magic index numbers.

* nrf/modules/machine/uart: Fix off-by-one error.

For nrf51:
.text: -40 bytes

* nrf/modules/machine/rtcounter: Update for nrfx HAL.

* nrf/modules/machine/i2c: Reduce RAM consumption.

Reductions for the nrf51:
flash: -108 bytes
RAM:   -72 bytes

* nrf/mpconfigport: Avoid unnecessary root pointers.

This saves 92 bytes of RAM.

* nrf: Support SoftDevice with nrfx HAL.

* nrf: Add NVMC peripheral (microbitfs) support.

There is no support yet for a SoftDevice.

It also fixes a potentially serious bug in start_index generation.

* nrf/modules/machine/spi: Optimize SPI peripheral.

nrf51:
text: -340 bytes
data: -72  bytes

nrf52:
text: -352 bytes
data: -108 bytes

* nrf/modules/random: Forgot to commit header file.

* nrf: Make nrfx_config.h universal for all boards.

* nrf: Use SoftDevice API for flash access when built for SD

* nrf/drivers/bluetooth: Remove legacy HAL driver includes.

These were not used anymore so can be removed.

* ports/nrf/microbit: Port microbit targets to nrfx HAL

Initial port of microbit modules to use nrfx HAL layer.
Tested display/image and modmusic on micro:bit to verify that
softpwm and ticker for nrf51 is working as expected.

Changing IRQ priority on timer to priority 2, as 1 might collide if
used side by side of SD110 BLE stack.

The patch reserves Timer1 peripheral compile time. This is not ideal
and should be resolved in seperate task.

* nrf/boards/microbit: Remove custom nrfx_config.h from microbit target, adding disablement of timer1 if softpwm is enabled.

* nrf/adc: Update ADC module to use nrfx

* nrf/modules/machine/pwm: Updating machine PWM module to use nrfx HAL driver.

examples/nrf52_pwm.py and examples/nrf52_servo.py tested on pca10040.

* nrf: Removing hal folder and boards nrf5x_hal_conf.h headers.

* nrf/nrfx_glue: Adding direct NVIC access for S110 BLE stack

If SoftDevice s110 has not yet been initialized, the IRQ will not be forwarded to
the application using the sd_nvic* function calls. Hence, direct access to cmsi
nvic functions are used instead if SoftDevice is not enabled.

* nrf/drivers/ticker: Setting IRQ priority 3 on Timer1

SoftDevice fails to initilize if Timer1 has been configured to priority
level 2 before enabling the SD. The timer is set to priority 1, higher than BLE
stack in order to provide better quality of music rendering when used with the
music module. This might be too high, time will show.

* nrf/examples: Updating ubluepy_temp after moving RTCounter to nrfx.

* nrf: delete duplicate files from device folder which can be located in nrfx/mdk.

* nrf/Makefile: Fetch system files from nrfx.

Testing on each device sub-variant to figure out which system file to
use. Reason for this is that nrf52.c is actually defining nrf52832.

Removing NRF_DEFINES parameter setting the device in use into the
same sub-variant test, as NRF52 is unique to nrf52832 when using nrfx.
Without this exclusion of -DNRF52 in compilation for nrf52840, the
device will be interpreted as a nrf52, hence nrf52832.

Also, changing name on variable SRC_NRF_HAL to SRC_NRFX_HAL to
explicitly tell the origin of the file.

* nrf: Updating device #ifdefs to be more open to non-nrf51 targets.

* nrf/modules/machine/uart: Removing second instance of UART for nrf52840 as it only has one non-DMA variant.

* nrf/device: Removing system files as these are now used from nrfx/mdk

* nrf: Moving startup files in device one level up as there is no need for deep hierarchy.

* nrf: Use NRF52_SERIES defined in nrfx/mdk/nrf.h as define value when testing for both nrf52(832) and nrf52840 variants.

* nrf/modules/machine/uart: Enable UART RX by default

Enable rx by default after intiialization of the peripheral.
Else, the nrfx driver will re-enable rx for each byte read
on uart REPL, clearing the EVENT_RXDRDY before second byte,
which again will make second byte get lost and read will get stuck.

This happens if the bytes are transmitted nrf(51) while still
processing the previous byte. Not seen on nrf52, but should
also become an issue at higher speeds.

This patch sets rx to always be enabled. Hence, not clearing the event
between read bytes, and it will be able to detect next byte recieved
upon finishing the first.

* nrf/modules/machine/timer: Fixing defines excluding Timer1 if ticker/softpwm is used.

* nrf: Switching import form mpconfigboard.h to mpconfigport.h in nrfx_config.h as mpconfigboard.h might define default values for defines not set by board specific header.

* nrf/modules/machine/i2c: nrfx integration fixes

Increasing speed to 400K.

Returning Address NACK's as MP error code; MP_ENODEV.

Returning MP_ETIMEOUT on all other error codes from TWI nrfx driver
except the ANACK.

Enabling and disabling the TWI peripheral before and after each transaction.

* nrf/examples: Updating ssd1306_mod.py to split framebuffer transfer into multiple chunks

* nrf/modules/machine/i2c: Return MP_EIO error if Data NACK occurs.

* nrf: Addressing review comments.

* nrf: Updating git submodule and users to nrfx v1.0.0.

* nrf/modules/machine/adc: Update adc module to follow v1.0.0 nrfx API.

* nrf/modules/machine/spi: Implement init and deinit functions

Extending SPI objects with a config member such that
configuration can be kept between new() and init().

Moving initialization done in new() to common init
function shared between the module functions.

If SPI is already configured, the SPI peripheral will
be uninitialized before initalized again.

Adding logic to handle initialization of polarity and
phase. As well, updating default speed to 1M from 500K.

* nrf/modules/machine: Removing unused nrfx includes in machine module header files

.gitmodules

@@ -15,3 +15,6 @@
 	path = lib/stm32lib
 	url = https://github.com/micropython/stm32lib
 	branch = work-F4-1.13.1+F7-1.5.0+L4-1.3.0
+[submodule "lib/nrfx"]
+	path = lib/nrfx
+	url = https://github.com/NordicSemiconductor/nrfx.git

nrfx @ cf78ebfe

+Subproject commit cf78ebfea1719d85cf4018fe6c08cc73fe5ec719

ports/nrf/Makefile

@@ -41,16 +41,10 @@ MPY_TOOL = ../../tools/mpy-tool.py
 
 CROSS_COMPILE = arm-none-eabi-
 
-MCU_VARIANT_UPPER = $(shell echo $(MCU_VARIANT) | tr '[:lower:]' '[:upper:]')
-
 INC += -I.
 INC += -I../..
 INC += -I$(BUILD)
 INC += -I./../../lib/cmsis/inc
-INC += -I./device
-INC += -I./device/$(MCU_VARIANT)
-INC += -I./hal
-INC += -I./hal/$(MCU_VARIANT)
 INC += -I./modules/machine
 INC += -I./modules/ubluepy
 INC += -I./modules/music
@@ -59,8 +53,29 @@ INC += -I./modules/ble
 INC += -I../../lib/mp-readline
 INC += -I./drivers/bluetooth
 INC += -I./drivers
+INC += -I../../lib/nrfx/
+INC += -I../../lib/nrfx/drivers
+INC += -I../../lib/nrfx/drivers/include
+INC += -I../../lib/nrfx/mdk
+INC += -I../../lib/nrfx/hal
 
-NRF_DEFINES += -D$(MCU_VARIANT_UPPER)
+MCU_VARIANT_UPPER = $(shell echo $(MCU_VARIANT) | tr '[:lower:]' '[:upper:]')
+MCU_SUB_VARIANT_UPPER = $(shell echo $(MCU_SUB_VARIANT) | tr '[:lower:]' '[:upper:]')
+
+# Figure out correct system file to use base on chip sub-variant name.
+SYSTEM_C_SRC :=
+ifeq ($(MCU_SUB_VARIANT),nrf51822)
+	SYSTEM_C_SRC += $(addprefix lib/nrfx/mdk/, system_nrf51.c)
+        NRF_DEFINES += -D$(MCU_VARIANT_UPPER)
+else ifeq ($(MCU_SUB_VARIANT),nrf52832)
+	SYSTEM_C_SRC += $(addprefix lib/nrfx/mdk/, system_nrf52.c)
+        NRF_DEFINES += -D$(MCU_VARIANT_UPPER)
+else ifeq ($(MCU_SUB_VARIANT),nrf52840)
+	SYSTEM_C_SRC += $(addprefix lib/nrfx/mdk/, system_nrf52840.c)
+	# Do not pass MCU_VARIANT_UPPER flag, as NRF52 defines NRF52832 only.
+endif
+
+NRF_DEFINES += -D$(MCU_SUB_VARIANT_UPPER)
 NRF_DEFINES += -DCONFIG_GPIO_AS_PINRESET
 
 CFLAGS_CORTEX_M = -mthumb -mabi=aapcs -fsingle-precision-constant -Wdouble-promotion
@@ -140,28 +155,22 @@ SRC_LIB += $(addprefix lib/,\
 	oofatfs/option/unicode.c \
 	)
 
-SRC_HAL = $(addprefix hal/,\
-	hal_uart.c \
-	hal_uarte.c \
-	hal_spi.c \
-	hal_spie.c \
-	hal_time.c \
-	hal_rtc.c \
-	hal_timer.c \
-	hal_twi.c \
-	hal_adc.c \
-	hal_adce.c \
-	hal_temp.c \
-	hal_gpio.c \
-	hal_rng.c \
-	hal_nvmc.c \
+SRC_NRFX += $(addprefix lib/nrfx/drivers/src/,\
+	prs/nrfx_prs.c \
+	nrfx_uart.c \
+	nrfx_adc.c \
+	nrfx_saadc.c \
+	nrfx_rng.c \
+	nrfx_twi.c \
+	nrfx_spi.c \
+	nrfx_rtc.c \
+	nrfx_timer.c \
+	nrfx_pwm.c \
 	)
 
-ifeq ($(MCU_VARIANT), nrf52)
-SRC_HAL += $(addprefix hal/,\
-	hal_pwm.c \
+SRC_NRFX_HAL += $(addprefix lib/nrfx/hal/,\
+	nrf_nvmc.c \
 	)
-endif
 
 SRC_C += \
 	main.c \
@@ -170,6 +179,7 @@ SRC_C += \
 	gccollect.c \
 	pin_named_pins.c \
 	fatfs_port.c \
+	drivers/flash.c \
 	drivers/softpwm.c \
 	drivers/ticker.c \
 	drivers/bluetooth/ble_drv.c \
@@ -183,7 +193,7 @@ DRIVERS_SRC_C += $(addprefix modules/,\
 	machine/adc.c \
 	machine/pin.c \
 	machine/timer.c \
-	machine/rtc.c \
+	machine/rtcounter.c \
 	machine/pwm.c \
 	machine/led.c \
 	machine/temp.c \
@@ -207,9 +217,10 @@ DRIVERS_SRC_C += $(addprefix modules/,\
 	random/modrandom.c \
 	)
 
+# Custom micropython startup file with smaller interrupt vector table
+# than the file provided in nrfx.
 SRC_C += \
-	device/$(MCU_VARIANT)/system_$(MCU_SUB_VARIANT).c \
-	device/$(MCU_VARIANT)/startup_$(MCU_SUB_VARIANT).c \
+	device/startup_$(MCU_SUB_VARIANT).c \
 
 ifneq ($(FROZEN_MPY_DIR),)
 FROZEN_MPY_PY_FILES := $(shell find -L $(FROZEN_MPY_DIR) -type f -name '*.py')
@@ -218,8 +229,10 @@ endif
 
 OBJ += $(PY_O) $(addprefix $(BUILD)/, $(SRC_C:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(SRC_LIB:.c=.o))
-OBJ += $(addprefix $(BUILD)/, $(SRC_HAL:.c=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_NRFX:.c=.o))
+OBJ += $(addprefix $(BUILD)/, $(SRC_NRFX_HAL:.c=.o))
 OBJ += $(addprefix $(BUILD)/, $(DRIVERS_SRC_C:.c=.o))
+OBJ += $(addprefix $(BUILD)/, $(SYSTEM_C_SRC:.c=.o))
 OBJ += $(BUILD)/pins_gen.o
 
 $(BUILD)/$(FATFS_DIR)/ff.o: COPT += -Os

ports/nrf/boards/arduino_primo/mpconfigboard.h

@@ -35,7 +35,7 @@
 #define MICROPY_PY_MACHINE_HW_PWM   (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (1)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_ADC      (1)
 #define MICROPY_PY_MACHINE_TEMP     (1)

ports/nrf/boards/arduino_primo/nrf52_hal_conf.h

-#ifndef NRF52_HAL_CONF_H__
-#define NRF52_HAL_CONF_H__
-
-#define HAL_UART_MODULE_ENABLED
-#define HAL_SPI_MODULE_ENABLED
-#define HAL_TIME_MODULE_ENABLED
-#define HAL_PWM_MODULE_ENABLED
-#define HAL_RTC_MODULE_ENABLED
-#define HAL_TIMER_MODULE_ENABLED
-#define HAL_TWI_MODULE_ENABLED
-#define HAL_ADCE_MODULE_ENABLED
-#define HAL_TEMP_MODULE_ENABLED
-#define HAL_RNG_MODULE_ENABLED
-// #define HAL_UARTE_MODULE_ENABLED
-// #define HAL_SPIE_MODULE_ENABLED
-// #define HAL_TWIE_MODULE_ENABLED
-
-#endif // NRF52_HAL_CONF_H__

ports/nrf/boards/dvk_bl652/mpconfigboard.h

@@ -34,7 +34,7 @@
 #define MICROPY_PY_MACHINE_PWM      (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (1)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_ADC      (1)
 #define MICROPY_PY_MACHINE_TEMP     (1)

ports/nrf/boards/dvk_bl652/nrf52_hal_conf.h

-#ifndef NRF52_HAL_CONF_H__
-#define NRF52_HAL_CONF_H__
-
-#define HAL_UART_MODULE_ENABLED
-#define HAL_SPI_MODULE_ENABLED
-#define HAL_TIME_MODULE_ENABLED
-#define HAL_PWM_MODULE_ENABLED
-#define HAL_RTC_MODULE_ENABLED
-#define HAL_TIMER_MODULE_ENABLED
-#define HAL_TWI_MODULE_ENABLED
-#define HAL_ADCE_MODULE_ENABLED
-#define HAL_TEMP_MODULE_ENABLED
-#define HAL_RNG_MODULE_ENABLED
-// #define HAL_UARTE_MODULE_ENABLED
-// #define HAL_SPIE_MODULE_ENABLED
-// #define HAL_TWIE_MODULE_ENABLED
-
-#endif // NRF52_HAL_CONF_H__

ports/nrf/boards/feather52/mpconfigboard.h

@@ -34,7 +34,7 @@
 #define MICROPY_PY_MACHINE_HW_PWM   (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (1)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_ADC      (1)
 #define MICROPY_PY_MACHINE_TEMP     (1)

ports/nrf/boards/feather52/nrf52_hal_conf.h

-#ifndef NRF52_HAL_CONF_H__
-#define NRF52_HAL_CONF_H__
-
-#define HAL_UART_MODULE_ENABLED
-#define HAL_SPI_MODULE_ENABLED
-#define HAL_TIME_MODULE_ENABLED
-#define HAL_PWM_MODULE_ENABLED
-#define HAL_RTC_MODULE_ENABLED
-#define HAL_TIMER_MODULE_ENABLED
-#define HAL_TWI_MODULE_ENABLED
-#define HAL_ADCE_MODULE_ENABLED
-#define HAL_TEMP_MODULE_ENABLED
-#define HAL_RNG_MODULE_ENABLED
-// #define HAL_UARTE_MODULE_ENABLED
-// #define HAL_SPIE_MODULE_ENABLED
-// #define HAL_TWIE_MODULE_ENABLED
-
-#endif // NRF52_HAL_CONF_H__

ports/nrf/boards/microbit/modules/microbitdisplay.c

@@ -25,10 +25,10 @@
  */
 
 #include <string.h>
-#include "hal_gpio.h"
 #include "py/obj.h"
 #include "py/runtime.h"
 #include "py/gc.h"
+#include "nrf_gpio.h"
 #include "microbitimage.h"
 #include "microbitdisplay.h"
 #include "iters.h"
@@ -188,9 +188,9 @@ static const DisplayPoint display_map[COLUMN_COUNT][ROW_COUNT] = {
 
 static inline void displaySetPinsForRow(microbit_display_obj_t * p_display, uint8_t brightness) {
     if (brightness == 0) {
-        hal_gpio_out_clear(0, COLUMN_PINS_MASK & ~p_display->pins_for_brightness[brightness]);
+        nrf_gpio_port_out_clear(NRF_GPIO, COLUMN_PINS_MASK & ~p_display->pins_for_brightness[brightness]);
     } else {
-        hal_gpio_out_set(0, p_display->pins_for_brightness[brightness]);
+        nrf_gpio_pin_set(p_display->pins_for_brightness[brightness]);
     }
 }
 
@@ -219,9 +219,9 @@ static inline void displaySetPinsForRow(microbit_display_obj_t * p_display, uint
  */
 static void displayAdvanceRow(microbit_display_obj_t * p_display) {
     /* Clear all of the column bits */
-    hal_gpio_out_set(0, COLUMN_PINS_MASK);
+    nrf_gpio_port_out_set(NRF_GPIO, COLUMN_PINS_MASK);
     /* Clear the strobe bit for this row */
-    hal_gpio_pin_clear(0, p_display->strobe_row + MIN_ROW_PIN);
+    nrf_gpio_pin_clear(p_display->strobe_row + MIN_ROW_PIN);
 
     /* Move to the next row.  Before this, "this row" refers to the row
      * manipulated by the previous invocation of this function.  After this,
@@ -247,9 +247,9 @@ static void displayAdvanceRow(microbit_display_obj_t * p_display) {
         (void)brightness;
     }
     /* Enable the strobe bit for this row */
-    hal_gpio_pin_set(0, p_display->strobe_row + MIN_ROW_PIN);
+    nrf_gpio_pin_set(p_display->strobe_row + MIN_ROW_PIN);
     /* Enable the column bits for all pins that need to be on. */
-    hal_gpio_out_clear(0, p_display->pins_for_brightness[MAX_BRIGHTNESS]);
+    nrf_gpio_port_out_clear(NRF_GPIO, p_display->pins_for_brightness[MAX_BRIGHTNESS]);
 }
 
 static const uint16_t render_timings[] =
@@ -458,7 +458,7 @@ mp_obj_t microbit_display_off_func(mp_obj_t obj) {
     self->active = false;
     /* Disable the row strobes, allowing the columns to be used freely for
      * GPIO. */
-    hal_gpio_out_clear(0, ROW_PINS_MASK);
+    nrf_gpio_port_out_clear(0, ROW_PINS_MASK);
     /* Free pins for other uses */
 /*
     microbit_obj_pin_free(&microbit_p3_obj);
@@ -571,6 +571,6 @@ microbit_display_obj_t microbit_display_obj = {
 void microbit_display_init(void) {
     //  Set pins as output.
     for (int i = MIN_COLUMN_PIN; i <= MAX_ROW_PIN; i++) {
-        hal_gpio_cfg_pin(0, i, HAL_GPIO_MODE_OUTPUT, HAL_GPIO_PULL_DOWN);
+        nrf_gpio_cfg_output(i);
     }
 }

ports/nrf/boards/microbit/modules/modmicrobit.c

@@ -32,7 +32,7 @@
 #include "microbitimage.h"
 #include "softpwm.h"
 #include "ticker.h"
-#include "hal_temp.h"
+#include "nrf_temp.h"
 
 extern uint32_t ticks;
 
@@ -97,11 +97,11 @@ STATIC mp_obj_t microbit_panic(mp_uint_t n_args, const mp_obj_t *args) {
 MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(microbit_panic_obj, 0, 1, microbit_panic);
 
 STATIC mp_obj_t microbit_temperature(void) {
-    int temp = hal_temp_read();
+    int temp = nrf_temp_read();
 #if MICROPY_FLOAT_IMPL == MICROPY_FLOAT_IMPL_FLOAT
-    return mp_obj_new_float(temp);
+    return mp_obj_new_float(temp / 4);
 #else
-    return mp_obj_new_int(temp);
+    return mp_obj_new_int(temp / 4);
 #endif
 }
 MP_DEFINE_CONST_FUN_OBJ_0(microbit_temperature_obj, microbit_temperature);

ports/nrf/boards/microbit/mpconfigboard.h

@@ -35,10 +35,11 @@
 #define MICROPY_PY_MACHINE_SOFT_PWM (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (1)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_ADC      (1)
 #define MICROPY_PY_MACHINE_TEMP     (1)
+#define MICROPY_PY_HW_RNG           (1)
 
 #define MICROPY_HW_HAS_LED          (0)
 #define MICROPY_HW_HAS_SWITCH       (0)

ports/nrf/boards/microbit/nrf51_hal_conf.h

-#ifndef NRF51_HAL_CONF_H__
-#define NRF51_HAL_CONF_H__
-
-#define HAL_UART_MODULE_ENABLED
-#define HAL_SPI_MODULE_ENABLED
-#define HAL_TIME_MODULE_ENABLED
-#define HAL_RTC_MODULE_ENABLED
-#define HAL_TIMER_MODULE_ENABLED
-#define HAL_TWI_MODULE_ENABLED
-#define HAL_ADC_MODULE_ENABLED
-#define HAL_TEMP_MODULE_ENABLED
-#define HAL_RNG_MODULE_ENABLED
-
-#endif // NRF51_HAL_CONF_H__

ports/nrf/boards/pca10000/mpconfigboard.h

@@ -33,7 +33,7 @@
 #define MICROPY_PY_MACHINE_UART     (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (0)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (0)
 #define MICROPY_PY_MACHINE_ADC      (0)
 #define MICROPY_PY_MACHINE_TEMP     (1)

ports/nrf/boards/pca10000/nrf51_hal_conf.h

-#ifndef NRF51_HAL_CONF_H__
-#define NRF51_HAL_CONF_H__
-
-#define HAL_UART_MODULE_ENABLED
-#define HAL_RTC_MODULE_ENABLED
-#define HAL_TIMER_MODULE_ENABLED
-#define HAL_TIME_MODULE_ENABLED
-#define HAL_TEMP_MODULE_ENABLED
-#define HAL_RNG_MODULE_ENABLED
-
-#endif // NRF51_HAL_CONF_H__

ports/nrf/boards/pca10001/mpconfigboard.h

@@ -33,7 +33,7 @@
 #define MICROPY_PY_MACHINE_UART     (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (0)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_ADC      (1)
 #define MICROPY_PY_MACHINE_TEMP     (1)

ports/nrf/boards/pca10001/nrf51_hal_conf.h

-#ifndef NRF51_HAL_CONF_H__
-#define NRF51_HAL_CONF_H__
-
-#define HAL_UART_MODULE_ENABLED
-#define HAL_SPI_MODULE_ENABLED
-#define HAL_TIME_MODULE_ENABLED
-#define HAL_RTC_MODULE_ENABLED
-#define HAL_TIMER_MODULE_ENABLED
-#define HAL_TWI_MODULE_ENABLED
-#define HAL_ADC_MODULE_ENABLED
-#define HAL_TEMP_MODULE_ENABLED
-#define HAL_RNG_MODULE_ENABLED
-
-#endif // NRF51_HAL_CONF_H__

ports/nrf/boards/pca10028/mpconfigboard.h

@@ -33,7 +33,7 @@
 #define MICROPY_PY_MACHINE_UART     (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (1)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_ADC      (1)
 #define MICROPY_PY_MACHINE_TEMP     (1)

ports/nrf/boards/pca10028/nrf51_hal_conf.h

-#ifndef NRF51_HAL_CONF_H__
-#define NRF51_HAL_CONF_H__
-
-#define HAL_UART_MODULE_ENABLED
-#define HAL_SPI_MODULE_ENABLED
-#define HAL_TIME_MODULE_ENABLED
-#define HAL_RTC_MODULE_ENABLED
-#define HAL_TIMER_MODULE_ENABLED
-#define HAL_TWI_MODULE_ENABLED
-#define HAL_ADC_MODULE_ENABLED
-#define HAL_TEMP_MODULE_ENABLED
-#define HAL_RNG_MODULE_ENABLED
-
-#endif // NRF51_HAL_CONF_H__

ports/nrf/boards/pca10031/mpconfigboard.h

@@ -33,7 +33,7 @@
 #define MICROPY_PY_MACHINE_UART     (1)
 #define MICROPY_PY_MACHINE_HW_SPI   (1)
 #define MICROPY_PY_MACHINE_TIMER    (1)
-#define MICROPY_PY_MACHINE_RTC      (1)
+#define MICROPY_PY_MACHINE_RTCOUNTER (1)
 #define MICROPY_PY_MACHINE_I2C      (1)
 #define MICROPY_PY_MACHINE_ADC      (1)
 #define MICROPY_PY_MACHINE_TEMP     (1)