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Posted to commits@nuttx.apache.org by xi...@apache.org on 2023/10/23 06:28:33 UTC
[nuttx] branch master updated: boards/stm32: add support to STM32F401RC-RS485 board
This is an automated email from the ASF dual-hosted git repository.
xiaoxiang pushed a commit to branch master
in repository https://gitbox.apache.org/repos/asf/nuttx.git
The following commit(s) were added to refs/heads/master by this push:
new 21ba49408c boards/stm32: add support to STM32F401RC-RS485 board
21ba49408c is described below
commit 21ba49408ccc3cda0a9a59fd1dd2475651eaab3f
Author: Rodrigo Sim <rc...@gmail.com>
AuthorDate: Sat Oct 14 17:11:19 2023 -0300
boards/stm32: add support to STM32F401RC-RS485 board
The STM32F401RC-RS485 is a board with RS485 support, SD Card, buttons,
leds, temperature sensor, adc and etc.
Signed-off-by: Rodrigo Sim rcsim10@gmail.com
---
boards/Kconfig | 14 +
boards/arm/stm32/stm32f401rc-rs485/CMakeLists.txt | 21 ++
boards/arm/stm32/stm32f401rc-rs485/Kconfig | 8 +
.../stm32/stm32f401rc-rs485/configs/nsh/defconfig | 48 +++
boards/arm/stm32/stm32f401rc-rs485/include/board.h | 401 +++++++++++++++++++++
.../arm/stm32/stm32f401rc-rs485/scripts/Make.defs | 43 +++
.../arm/stm32/stm32f401rc-rs485/scripts/ld.script | 107 ++++++
.../arm/stm32/stm32f401rc-rs485/src/CMakeLists.txt | 35 ++
boards/arm/stm32/stm32f401rc-rs485/src/Make.defs | 36 ++
.../stm32/stm32f401rc-rs485/src/stm32_appinit.c | 76 ++++
.../stm32/stm32f401rc-rs485/src/stm32_autoleds.c | 81 +++++
.../arm/stm32/stm32f401rc-rs485/src/stm32_boot.c | 85 +++++
.../stm32/stm32f401rc-rs485/src/stm32_bringup.c | 65 ++++
.../stm32f401rc-rs485/src/stm32f401rc-rs485.h | 309 ++++++++++++++++
14 files changed, 1329 insertions(+)
diff --git a/boards/Kconfig b/boards/Kconfig
index 800e01d091..d899ca8e0a 100644
--- a/boards/Kconfig
+++ b/boards/Kconfig
@@ -1604,6 +1604,16 @@ config ARCH_BOARD_NUCLEO_F401RE
This is a minimal configuration that supports low-level test of the
Nucleo F401RE in the NuttX source tree.
+config ARCH_BOARD_STM32F401RC_RS485
+ bool "STM32F401RC-RS485 Board"
+ depends on ARCH_CHIP_STM32F401RC
+ select ARCH_HAVE_LEDS
+ select ARCH_HAVE_BUTTONS
+ select ARCH_HAVE_IRQBUTTONS
+ ---help---
+ This is a minimal configuration that supports low-level test of the
+ STM32F401RC-RS485 in the NuttX source tree.
+
config ARCH_BOARD_NUCLEO_F410RB
bool "STM32F410 Nucleo F410RB"
depends on ARCH_CHIP_STM32F410RB
@@ -3144,6 +3154,7 @@ config ARCH_BOARD
default "nucleo-f303ze" if ARCH_BOARD_NUCLEO_F303ZE
default "nucleo-f334r8" if ARCH_BOARD_NUCLEO_F334R8
default "nucleo-f4x1re" if ARCH_BOARD_NUCLEO_F401RE || ARCH_BOARD_NUCLEO_F411RE
+ default "stm32f401rc-rs485" if ARCH_BOARD_STM32F401RC_RS485
default "nucleo-f429zi" if ARCH_BOARD_NUCLEO_F429ZI
default "nucleo-f446re" if ARCH_BOARD_NUCLEO_F446RE
default "nucleo-f410rb" if ARCH_BOARD_NUCLEO_F410RB
@@ -3860,6 +3871,9 @@ endif
if ARCH_BOARD_NUCLEO_F401RE || ARCH_BOARD_NUCLEO_F411RE
source "boards/arm/stm32/nucleo-f4x1re/Kconfig"
endif
+if ARCH_BOARD_STM32F401RC_RS485
+source "boards/arm/stm32/stm32f401rc-rs485/Kconfig"
+endif
if ARCH_BOARD_NUCLEO_F429ZI
source "boards/arm/stm32/nucleo-f429zi/Kconfig"
endif
diff --git a/boards/arm/stm32/stm32f401rc-rs485/CMakeLists.txt b/boards/arm/stm32/stm32f401rc-rs485/CMakeLists.txt
new file mode 100644
index 0000000000..6f0b58e2db
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/CMakeLists.txt
@@ -0,0 +1,21 @@
+# ##############################################################################
+# boards/arm/stm32/stm32f401rc-rs485/CMakeLists.txt
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more contributor
+# license agreements. See the NOTICE file distributed with this work for
+# additional information regarding copyright ownership. The ASF licenses this
+# file to you under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+#
+# ##############################################################################
+
+add_subdirectory(src)
diff --git a/boards/arm/stm32/stm32f401rc-rs485/Kconfig b/boards/arm/stm32/stm32f401rc-rs485/Kconfig
new file mode 100644
index 0000000000..9d05b0d826
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/Kconfig
@@ -0,0 +1,8 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+if ARCH_BOARD_STM32F401RC_RS485
+
+endif # ARCH_BOARD_STM32F401RC_RS485
diff --git a/boards/arm/stm32/stm32f401rc-rs485/configs/nsh/defconfig b/boards/arm/stm32/stm32f401rc-rs485/configs/nsh/defconfig
new file mode 100644
index 0000000000..38de140a62
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/configs/nsh/defconfig
@@ -0,0 +1,48 @@
+#
+# This file is autogenerated: PLEASE DO NOT EDIT IT.
+#
+# You can use "make menuconfig" to make any modifications to the installed .config file.
+# You can then do "make savedefconfig" to generate a new defconfig file that includes your
+# modifications.
+#
+# CONFIG_ARCH_FPU is not set
+# CONFIG_NSH_ARGCAT is not set
+# CONFIG_NSH_CMDOPT_HEXDUMP is not set
+# CONFIG_NSH_DISABLE_IFCONFIG is not set
+# CONFIG_NSH_DISABLE_PS is not set
+CONFIG_ARCH="arm"
+CONFIG_ARCH_BOARD="stm32f401rc-rs485"
+CONFIG_ARCH_BOARD_STM32F401RC_RS485=y
+CONFIG_ARCH_BUTTONS=y
+CONFIG_ARCH_CHIP="stm32"
+CONFIG_ARCH_CHIP_STM32=y
+CONFIG_ARCH_CHIP_STM32F401RC=y
+CONFIG_ARCH_INTERRUPTSTACK=2048
+CONFIG_ARCH_STACKDUMP=y
+CONFIG_BOARD_LOOPSPERMSEC=8499
+CONFIG_BUILTIN=y
+CONFIG_HAVE_CXX=y
+CONFIG_HAVE_CXXINITIALIZE=y
+CONFIG_INIT_ENTRYPOINT="nsh_main"
+CONFIG_INTELHEX_BINARY=y
+CONFIG_NSH_BUILTIN_APPS=y
+CONFIG_NSH_FILEIOSIZE=512
+CONFIG_NSH_LINELEN=64
+CONFIG_NSH_READLINE=y
+CONFIG_PREALLOC_TIMERS=4
+CONFIG_RAM_SIZE=98304
+CONFIG_RAM_START=0x20000000
+CONFIG_RAW_BINARY=y
+CONFIG_RR_INTERVAL=200
+CONFIG_SCHED_WAITPID=y
+CONFIG_SPI=y
+CONFIG_START_DAY=5
+CONFIG_START_MONTH=5
+CONFIG_START_YEAR=2014
+CONFIG_STM32_JTAG_SW_ENABLE=y
+CONFIG_STM32_OTGFS=y
+CONFIG_STM32_PWR=y
+CONFIG_STM32_USART2=y
+CONFIG_SYSTEM_NSH=y
+CONFIG_TASK_NAME_SIZE=0
+CONFIG_USART2_SERIAL_CONSOLE=y
diff --git a/boards/arm/stm32/stm32f401rc-rs485/include/board.h b/boards/arm/stm32/stm32f401rc-rs485/include/board.h
new file mode 100644
index 0000000000..947d49d8bc
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/include/board.h
@@ -0,0 +1,401 @@
+/****************************************************************************
+ * boards/arm/stm32/stm32f401rc-rs485/include/board.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership. The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __BOARDS_ARM_STM32F401RC_RS485_INCLUDE_BOARD_H
+#define __BOARDS_ARM_STM32F401RC_RS485_INCLUDE_BOARD_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#ifndef __ASSEMBLY__
+# include <stdint.h>
+#endif
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* Clocking *****************************************************************/
+
+/* The STM32F401RC-RS485 supports both HSE and LSE crystals (X2 and X3).
+ * However, as shipped, the X2 and X3 crystals are not populated.
+ * Therefore the Nucleo-F401RE will need to run off the 16MHz HSI clock.
+ *
+ * System Clock source : PLL (HSI)
+ * SYSCLK(Hz) : 84000000 Determined by PLL
+ * configuration
+ * HCLK(Hz) : 84000000 (STM32_RCC_CFGR_HPRE)
+ * AHB Prescaler : 1 (STM32_RCC_CFGR_HPRE)
+ * APB1 Prescaler : 2 (STM32_RCC_CFGR_PPRE1)
+ * APB2 Prescaler : 1 (STM32_RCC_CFGR_PPRE2)
+ * HSI Frequency(Hz) : 16000000 (nominal)
+ * PLLM : 16 (STM32_PLLCFG_PLLM)
+ * PLLN : 336 (STM32_PLLCFG_PLLN)
+ * PLLP : 4 (STM32_PLLCFG_PLLP)
+ * PLLQ : 7 (STM32_PLLCFG_PPQ)
+ * Flash Latency(WS) : 5
+ * Prefetch Buffer : OFF
+ * Instruction cache : ON
+ * Data cache : ON
+ * Require 48MHz for USB OTG FS, : Enabled
+ * SDIO and RNG clock
+ */
+
+/* HSI - 16 MHz RC factory-trimmed
+ * LSI - 32 KHz RC
+ * HSE - not installed
+ * LSE - not installed
+ */
+
+#define STM32_HSI_FREQUENCY 16000000ul
+#define STM32_LSI_FREQUENCY 32000
+#define STM32_BOARD_USEHSI 1
+
+/* Main PLL Configuration.
+ *
+ * Formulae:
+ *
+ * VCO input frequency = PLL input clock frequency / PLLM,
+ * 2 <= PLLM <= 63
+ * VCO output frequency = VCO input frequency × PLLN,
+ * 192 <= PLLN <= 432
+ * PLL output clock frequency = VCO frequency / PLLP,
+ * PLLP = 2, 4, 6, or 8
+ * USB OTG FS clock frequency = VCO frequency / PLLQ,
+ * 2 <= PLLQ <= 15
+ *
+ * We would like to have SYSYCLK=84MHz and we must have the USB clock= 48MHz.
+ * Some possible solutions include:
+ *
+ * PLLN=210 PLLM=5 PLLP=8 PLLQ=14 SYSCLK=84000000 OTGFS=48000000
+ * PLLN=210 PLLM=10 PLLP=4 PLLQ=7 SYSCLK=84000000 OTGFS=48000000
+ * PLLN=336 PLLM=8 PLLP=8 PLLQ=14 SYSCLK=84000000 OTGFS=48000000
+ * PLLN=336 PLLM=16 PLLP=4 PLLQ=7 SYSCLK=84000000 OTGFS=48000000
+ * PLLN=420 PLLM=10 PLLP=8 PLLQ=14 SYSCLK=84000000 OTGFS=48000000
+ * PLLN=420 PLLM=20 PLLP=4 PLLQ=7 SYSCLK=84000000 OTGFS=48000000
+ *
+ * We will configure like this
+ *
+ * PLL source is HSI
+ * PLL_VCO = (STM32_HSI_FREQUENCY / PLLM) * PLLN
+ * = (16,000,000 / 16) * 336
+ * = 336,000,000
+ * SYSCLK = PLL_VCO / PLLP
+ * = 336,000,000 / 4 = 84,000,000
+ * USB OTG FS and SDIO Clock
+ * = PLL_VCO / PLLQ
+ * = 336,000,000 / 7 = 48,000,000
+ *
+ * REVISIT: Trimming of the HSI is not yet supported.
+ */
+
+#define STM32_PLLCFG_PLLM RCC_PLLCFG_PLLM(16)
+#define STM32_PLLCFG_PLLN RCC_PLLCFG_PLLN(336)
+#define STM32_PLLCFG_PLLP RCC_PLLCFG_PLLP_4
+#define STM32_PLLCFG_PLLQ RCC_PLLCFG_PLLQ(7)
+
+#define STM32_SYSCLK_FREQUENCY 84000000ul
+
+/* AHB clock (HCLK) is SYSCLK (84MHz) */
+
+#define STM32_RCC_CFGR_HPRE RCC_CFGR_HPRE_SYSCLK /* HCLK = SYSCLK / 1 */
+#define STM32_HCLK_FREQUENCY STM32_SYSCLK_FREQUENCY
+
+/* APB1 clock (PCLK1) is HCLK/2 (42MHz) */
+
+#define STM32_RCC_CFGR_PPRE1 RCC_CFGR_PPRE1_HCLKd2 /* PCLK1 = HCLK / 2 */
+#define STM32_PCLK1_FREQUENCY (STM32_HCLK_FREQUENCY/2)
+
+/* Timers driven from APB1 will be twice PCLK1 */
+
+/* REVISIT */
+
+#define STM32_APB1_TIM2_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM3_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM4_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM5_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM6_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM7_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM12_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM13_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB1_TIM14_CLKIN (2*STM32_PCLK1_FREQUENCY)
+
+/* APB2 clock (PCLK2) is HCLK (84MHz) */
+
+#define STM32_RCC_CFGR_PPRE2 RCC_CFGR_PPRE2_HCLK /* PCLK2 = HCLK / 1 */
+#define STM32_PCLK2_FREQUENCY (STM32_HCLK_FREQUENCY/1)
+
+/* Timers driven from APB2 will be twice PCLK2 */
+
+/* REVISIT */
+
+#define STM32_APB2_TIM1_CLKIN (2*STM32_PCLK2_FREQUENCY)
+#define STM32_APB2_TIM8_CLKIN (2*STM32_PCLK2_FREQUENCY)
+#define STM32_APB2_TIM9_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB2_TIM10_CLKIN (2*STM32_PCLK1_FREQUENCY)
+#define STM32_APB2_TIM11_CLKIN (2*STM32_PCLK1_FREQUENCY)
+
+/* Timer Frequencies, if APBx is set to 1, frequency is same to APBx
+ * otherwise frequency is 2xAPBx.
+ * Note: TIM1,8 are on APB2, others on APB1
+ */
+
+/* REVISIT */
+
+#define BOARD_TIM1_FREQUENCY (2*STM32_PCLK2_FREQUENCY)
+#define BOARD_TIM2_FREQUENCY (2*STM32_PCLK1_FREQUENCY)
+#define BOARD_TIM3_FREQUENCY (2*STM32_PCLK1_FREQUENCY)
+#define BOARD_TIM4_FREQUENCY (2*STM32_PCLK1_FREQUENCY)
+#define BOARD_TIM5_FREQUENCY (2*STM32_PCLK1_FREQUENCY)
+#define BOARD_TIM6_FREQUENCY (2*STM32_PCLK1_FREQUENCY)
+#define BOARD_TIM7_FREQUENCY (2*STM32_PCLK1_FREQUENCY)
+#define BOARD_TIM8_FREQUENCY (2*STM32_PCLK2_FREQUENCY)
+
+/* SDIO dividers. Note that slower clocking is required when DMA is disabled
+ * in order to avoid RX overrun/TX underrun errors due to delayed responses
+ * to service FIFOs in interrupt driven mode. These values have not been
+ * tuned!!!
+ *
+ * HCLK=72MHz, SDIOCLK=72MHz, SDIO_CK=HCLK/(178+2)=400 KHz
+ */
+
+/* REVISIT */
+
+#define SDIO_INIT_CLKDIV (178 << SDIO_CLKCR_CLKDIV_SHIFT)
+
+/* DMA ON: HCLK=72 MHz, SDIOCLK=72MHz, SDIO_CK=HCLK/(2+2)=18 MHz
+ * DMA OFF: HCLK=72 MHz, SDIOCLK=72MHz, SDIO_CK=HCLK/(3+2)=14.4 MHz
+ */
+
+/* REVISIT */
+
+#ifdef CONFIG_SDIO_DMA
+# define SDIO_MMCXFR_CLKDIV (2 << SDIO_CLKCR_CLKDIV_SHIFT)
+#else
+# define SDIO_MMCXFR_CLKDIV (3 << SDIO_CLKCR_CLKDIV_SHIFT)
+#endif
+
+/* DMA ON: HCLK=72 MHz, SDIOCLK=72MHz, SDIO_CK=HCLK/(1+2)=24 MHz
+ * DMA OFF: HCLK=72 MHz, SDIOCLK=72MHz, SDIO_CK=HCLK/(3+2)=14.4 MHz
+ */
+
+/* REVISIT */
+
+#ifdef CONFIG_SDIO_DMA
+# define SDIO_SDXFR_CLKDIV (1 << SDIO_CLKCR_CLKDIV_SHIFT)
+#else
+# define SDIO_SDXFR_CLKDIV (3 << SDIO_CLKCR_CLKDIV_SHIFT)
+#endif
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+#ifndef __ASSEMBLY__
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C"
+{
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* __ASSEMBLY__ */
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* DMA Channel/Stream Selections ********************************************/
+
+/* Stream selections are arbitrary for now but might become important in
+ * the future is we set aside more DMA channels/streams.
+ *
+ * SDIO DMA
+ * DMAMAP_SDIO_1 = Channel 4, Stream 3 <- may later be used by SPI DMA
+ * DMAMAP_SDIO_2 = Channel 4, Stream 6
+ */
+
+#define DMAMAP_SDIO DMAMAP_SDIO_1
+
+/* Need to VERIFY fwb */
+
+#define DMACHAN_SPI1_RX DMAMAP_SPI1_RX_1
+#define DMACHAN_SPI1_TX DMAMAP_SPI1_TX_1
+#define DMACHAN_SPI2_RX DMAMAP_SPI2_RX
+#define DMACHAN_SPI2_TX DMAMAP_SPI2_TX
+
+/* Alternate function pin selections ****************************************/
+
+/* USART1:
+ * RXD: PA10 CN9 pin 3, CN10 pin 33
+ * PB7 CN7 pin 21
+ * TXD: PA9 CN5 pin 1, CN10 pin 21
+ * PB6 CN5 pin 3, CN10 pin 17
+ */
+
+#if 1
+# define GPIO_USART1_RX GPIO_USART1_RX_1 /* PA10 */
+# define GPIO_USART1_TX GPIO_USART1_TX_1 /* PA9 */
+#else
+# define GPIO_USART1_RX GPIO_USART1_RX_2 /* PB7 */
+# define GPIO_USART1_TX GPIO_USART1_TX_2 /* PB6 */
+#endif
+
+/* USART2:
+ * RXD: PA3 CN9 pin 1 (See SB13, 14, 62, 63). CN10 pin 37
+ * PD6
+ * TXD: PA2 CN9 pin 2(See SB13, 14, 62, 63). CN10 pin 35
+ * PD5
+ */
+
+#define GPIO_USART2_RX GPIO_USART2_RX_1 /* PA3 */
+#define GPIO_USART2_TX GPIO_USART2_TX_1 /* PA2 */
+#define GPIO_USART2_RTS GPIO_USART2_RTS_2
+#define GPIO_USART2_CTS GPIO_USART2_CTS_2
+
+/* USART6:
+ * RXD: PC7 CN5 pin2, CN10 pin 19
+ * PA12 CN10, pin 12
+ * TXD: PC6 CN10, pin 4
+ * PA11 CN10, pin 14
+ */
+
+#define GPIO_USART6_RX GPIO_USART6_RX_1 /* PC7 */
+#define GPIO_USART6_TX GPIO_USART6_TX_1 /* PC6 */
+
+/* UART RX DMA configurations */
+
+#define DMAMAP_USART1_RX DMAMAP_USART1_RX_2
+#define DMAMAP_USART6_RX DMAMAP_USART6_RX_2
+
+/* I2C
+ *
+ * The optional _GPIO configurations allow the I2C driver to manually
+ * reset the bus to clear stuck slaves. They match the pin configuration,
+ * but are normally-high GPIOs.
+ */
+
+#define GPIO_I2C1_SCL GPIO_I2C1_SCL_2
+#define GPIO_I2C1_SDA GPIO_I2C1_SDA_2
+#define GPIO_I2C1_SCL_GPIO \
+ (GPIO_OUTPUT|GPIO_OPENDRAIN|GPIO_SPEED_50MHz|GPIO_OUTPUT_SET|GPIO_PORTB|GPIO_PIN8)
+#define GPIO_I2C1_SDA_GPIO \
+ (GPIO_OUTPUT|GPIO_OPENDRAIN|GPIO_SPEED_50MHz|GPIO_OUTPUT_SET|GPIO_PORTB|GPIO_PIN9)
+
+#define GPIO_I2C2_SCL GPIO_I2C2_SCL_1
+#define GPIO_I2C2_SDA GPIO_I2C2_SDA_1
+#define GPIO_I2C2_SCL_GPIO \
+ (GPIO_OUTPUT|GPIO_OPENDRAIN|GPIO_SPEED_50MHz|GPIO_OUTPUT_SET|GPIO_PORTB|GPIO_PIN10)
+#define GPIO_I2C2_SDA_GPIO \
+ (GPIO_OUTPUT|GPIO_OPENDRAIN|GPIO_SPEED_50MHz|GPIO_OUTPUT_SET|GPIO_PORTB|GPIO_PIN11)
+
+/* SPI
+ *
+ * There are sensors on SPI1, and SPI2 is connected to the FRAM.
+ */
+
+#define GPIO_SPI1_MISO GPIO_SPI1_MISO_1
+#define GPIO_SPI1_MOSI GPIO_SPI1_MOSI_1
+#define GPIO_SPI1_SCK GPIO_SPI1_SCK_1
+
+#define GPIO_SPI2_MISO GPIO_SPI2_MISO_1
+#define GPIO_SPI2_MOSI GPIO_SPI2_MOSI_1
+#define GPIO_SPI2_SCK GPIO_SPI2_SCK_2
+
+/* LEDs
+ *
+ * The Nucleo F401RE and F411RE boards provide a single user LED, LD2. LD2
+ * is the green LED connected to Arduino signal D13 corresponding to MCU I/O
+ * PA5 (pin 21) or PB13 (pin 34) depending on the STM32 target.
+ *
+ * - When the I/O is HIGH value, the LED is on.
+ * - When the I/O is LOW, the LED is off.
+ */
+
+/* LED index values for use with board_userled() */
+
+#define BOARD_LD2 0
+#define BOARD_NLEDS 1
+
+/* LED bits for use with board_userled_all() */
+
+#define BOARD_LD2_BIT (1 << BOARD_LD2)
+
+/* These LEDs are not used by the board port unless CONFIG_ARCH_LEDS is
+ * defined. In that case, the usage by the board port is defined in
+ * include/board.h and src/sam_leds.c. The LEDs are used to encode OS-related
+ * events as follows when the red LED (PE24) is available:
+ *
+ * SYMBOL Meaning LD2
+ * ------------------- ----------------------- -----------
+ * LED_STARTED NuttX has been started OFF
+ * LED_HEAPALLOCATE Heap has been allocated OFF
+ * LED_IRQSENABLED Interrupts enabled OFF
+ * LED_STACKCREATED Idle stack created ON
+ * LED_INIRQ In an interrupt No change
+ * LED_SIGNAL In a signal handler No change
+ * LED_ASSERTION An assertion failed No change
+ * LED_PANIC The system has crashed Blinking
+ * LED_IDLE MCU is is sleep mode Not used
+ *
+ * Thus if LD2, NuttX has successfully booted and is, apparently, running
+ * normally. If LD2 is flashing at approximately 2Hz, then a fatal error
+ * has been detected and the system has halted.
+ */
+
+#define LED_STARTED 0
+#define LED_HEAPALLOCATE 0
+#define LED_IRQSENABLED 0
+#define LED_STACKCREATED 1
+#define LED_INIRQ 2
+#define LED_SIGNAL 2
+#define LED_ASSERTION 2
+#define LED_PANIC 1
+
+/* Buttons
+ *
+ * B1 USER:
+ * the user button is connected to the I/O PC13 (pin 2) of the STM32
+ * microcontroller.
+ */
+
+#define BUTTON_USER 0
+#define NUM_BUTTONS 1
+
+#define BUTTON_USER_BIT (1 << BUTTON_USER)
+
+#define GPIO_TIM2_CH1IN (GPIO_TIM2_CH1IN_1 | GPIO_PULLUP)
+#define GPIO_TIM2_CH2IN (GPIO_TIM2_CH2IN_1 | GPIO_PULLUP)
+
+#endif /* __BOARDS_ARM_STM32F401RC_RS485_INCLUDE_BOARD_H */
diff --git a/boards/arm/stm32/stm32f401rc-rs485/scripts/Make.defs b/boards/arm/stm32/stm32f401rc-rs485/scripts/Make.defs
new file mode 100644
index 0000000000..88f3b074ce
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/scripts/Make.defs
@@ -0,0 +1,43 @@
+############################################################################
+# boards/arm/stm32/stm32f401rc-rs485/scripts/Make.defs
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership. The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+include $(TOPDIR)/.config
+include $(TOPDIR)/tools/Config.mk
+include $(TOPDIR)/arch/arm/src/armv7-m/Toolchain.defs
+
+ifeq ($(CONFIG_ARCH_CHIP_STM32F401RC),y)
+LDSCRIPT = ld.script
+endif
+
+ARCHSCRIPT += $(BOARD_DIR)$(DELIM)scripts$(DELIM)$(LDSCRIPT)
+
+ARCHPICFLAGS = -fpic -msingle-pic-base -mpic-register=r10
+
+CFLAGS := $(ARCHCFLAGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS) -pipe
+CPICFLAGS = $(ARCHPICFLAGS) $(CFLAGS)
+CXXFLAGS := $(ARCHCXXFLAGS) $(ARCHOPTIMIZATION) $(ARCHCPUFLAGS) $(ARCHXXINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS) -pipe
+CXXPICFLAGS = $(ARCHPICFLAGS) $(CXXFLAGS)
+CPPFLAGS := $(ARCHINCLUDES) $(ARCHDEFINES) $(EXTRAFLAGS)
+AFLAGS := $(CFLAGS) -D__ASSEMBLY__
+
+NXFLATLDFLAGS1 = -r -d -warn-common
+NXFLATLDFLAGS2 = $(NXFLATLDFLAGS1) -T$(TOPDIR)/binfmt/libnxflat/gnu-nxflat-pcrel.ld -no-check-sections
+LDNXFLATFLAGS = -e main -s 2048
+
diff --git a/boards/arm/stm32/stm32f401rc-rs485/scripts/ld.script b/boards/arm/stm32/stm32f401rc-rs485/scripts/ld.script
new file mode 100644
index 0000000000..e88b129682
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/scripts/ld.script
@@ -0,0 +1,107 @@
+/****************************************************************************
+ * boards/arm/stm32/stm32f401rc-rs485/scripts/ld.script
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership. The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/* The STM32F401RC has 128Kb of FLASH beginning at address 0x0800:0000 and
+ * 64Kb of SRAM beginning at address 0x2000:0000. When booting from FLASH,
+ * FLASH memory is aliased to address 0x0000:0000 where the code expects to
+ * begin execution by jumping to the entry point in the 0x0800:0000 address
+ * range.
+ */
+
+MEMORY
+{
+ flash (rx) : ORIGIN = 0x08000000, LENGTH = 128K
+ sram (rwx) : ORIGIN = 0x20000000, LENGTH = 64K
+}
+
+OUTPUT_ARCH(arm)
+EXTERN(_vectors)
+ENTRY(_stext)
+SECTIONS
+{
+ .text : {
+ _stext = ABSOLUTE(.);
+ *(.vectors)
+ *(.text .text.*)
+ *(.fixup)
+ *(.gnu.warning)
+ *(.rodata .rodata.*)
+ *(.gnu.linkonce.t.*)
+ *(.glue_7)
+ *(.glue_7t)
+ *(.got)
+ *(.gcc_except_table)
+ *(.gnu.linkonce.r.*)
+ _etext = ABSOLUTE(.);
+ } > flash
+
+ .init_section : {
+ _sinit = ABSOLUTE(.);
+ KEEP(*(SORT_BY_INIT_PRIORITY(.init_array.*) SORT_BY_INIT_PRIORITY(.ctors.*)))
+ KEEP(*(.init_array .ctors))
+ _einit = ABSOLUTE(.);
+ } > flash
+
+ .ARM.extab : {
+ *(.ARM.extab*)
+ } > flash
+
+ __exidx_start = ABSOLUTE(.);
+ .ARM.exidx : {
+ *(.ARM.exidx*)
+ } > flash
+ __exidx_end = ABSOLUTE(.);
+
+ _eronly = ABSOLUTE(.);
+
+ /* The STM32F401RC has 128Kb of SRAM beginning at the following address */
+
+ .data : {
+ _sdata = ABSOLUTE(.);
+ *(.data .data.*)
+ *(.gnu.linkonce.d.*)
+ CONSTRUCTORS
+ . = ALIGN(4);
+ _edata = ABSOLUTE(.);
+ } > sram AT > flash
+
+ .bss : {
+ _sbss = ABSOLUTE(.);
+ *(.bss .bss.*)
+ *(.gnu.linkonce.b.*)
+ *(COMMON)
+ . = ALIGN(4);
+ _ebss = ABSOLUTE(.);
+ } > sram
+
+ /* Stabs debugging sections. */
+ .stab 0 : { *(.stab) }
+ .stabstr 0 : { *(.stabstr) }
+ .stab.excl 0 : { *(.stab.excl) }
+ .stab.exclstr 0 : { *(.stab.exclstr) }
+ .stab.index 0 : { *(.stab.index) }
+ .stab.indexstr 0 : { *(.stab.indexstr) }
+ .comment 0 : { *(.comment) }
+ .debug_abbrev 0 : { *(.debug_abbrev) }
+ .debug_info 0 : { *(.debug_info) }
+ .debug_line 0 : { *(.debug_line) }
+ .debug_pubnames 0 : { *(.debug_pubnames) }
+ .debug_aranges 0 : { *(.debug_aranges) }
+}
diff --git a/boards/arm/stm32/stm32f401rc-rs485/src/CMakeLists.txt b/boards/arm/stm32/stm32f401rc-rs485/src/CMakeLists.txt
new file mode 100644
index 0000000000..9162a3204b
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/src/CMakeLists.txt
@@ -0,0 +1,35 @@
+# ##############################################################################
+# boards/arm/stm32/smt32f401rc-rs485/src/CMakeLists.txt
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more contributor
+# license agreements. See the NOTICE file distributed with this work for
+# additional information regarding copyright ownership. The ASF licenses this
+# file to you under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+#
+# ##############################################################################
+
+set(SRCS stm32_boot.c stm32_bringup.c)
+
+if(CONFIG_ARCH_LEDS)
+ list(APPEND SRCS stm32_autoleds.c)
+endif()
+
+if(CONFIG_BOARDCTL)
+ list(APPEND SRCS stm32_appinit.c)
+endif()
+
+target_sources(board PRIVATE ${SRCS})
+
+if(CONFIG_ARCH_CHIP_STM32F401RC)
+ set_property(GLOBAL PROPERTY LD_SCRIPT "${NUTTX_BOARD_DIR}/scripts/ld.script")
+endif()
diff --git a/boards/arm/stm32/stm32f401rc-rs485/src/Make.defs b/boards/arm/stm32/stm32f401rc-rs485/src/Make.defs
new file mode 100644
index 0000000000..ba63091126
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/src/Make.defs
@@ -0,0 +1,36 @@
+############################################################################
+# boards/arm/stm32/smt32f401rc-rs485/src/Make.defs
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership. The
+# ASF licenses this file to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance with the
+# License. You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+#
+############################################################################
+
+include $(TOPDIR)/Make.defs
+
+CSRCS = stm32_boot.c stm32_bringup.c
+
+
+ifeq ($(CONFIG_ARCH_LEDS),y)
+CSRCS += stm32_autoleds.c
+endif
+
+ifeq ($(CONFIG_BOARDCTL),y)
+CSRCS += stm32_appinit.c
+endif
+
+DEPPATH += --dep-path board
+VPATH += :board
+CFLAGS += ${INCDIR_PREFIX}$(TOPDIR)$(DELIM)arch$(DELIM)$(CONFIG_ARCH)$(DELIM)src$(DELIM)board$(DELIM)board
diff --git a/boards/arm/stm32/stm32f401rc-rs485/src/stm32_appinit.c b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_appinit.c
new file mode 100644
index 0000000000..cb000155e1
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_appinit.c
@@ -0,0 +1,76 @@
+/****************************************************************************
+ * boards/arm/stm32/stm32f401rc-rs485/src/stm32_appinit.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership. The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdint.h>
+
+#include "stm32f401rc-rs485.h"
+
+#include <nuttx/board.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_app_initialize
+ *
+ * Description:
+ * Perform application specific initialization. This function is never
+ * called directly from application code, but only indirectly via the
+ * (non-standard) boardctl() interface using the command BOARDIOC_INIT.
+ *
+ * Input Parameters:
+ * arg - The boardctl() argument is passed to the board_app_initialize()
+ * implementation without modification. The argument has no
+ * meaning to NuttX; the meaning of the argument is a contract
+ * between the board-specific initialization logic and the
+ * matching application logic. The value could be such things as a
+ * mode enumeration value, a set of DIP switch switch settings, a
+ * pointer to configuration data read from a file or serial FLASH,
+ * or whatever you would like to do with it. Every implementation
+ * should accept zero/NULL as a default configuration.
+ *
+ * Returned Value:
+ * Zero (OK) is returned on success; a negated errno value is returned on
+ * any failure to indicate the nature of the failure.
+ *
+ ****************************************************************************/
+
+int board_app_initialize(uintptr_t arg)
+{
+#ifdef CONFIG_BOARD_LATE_INITIALIZE
+ return OK;
+#else
+ /* Perform board initialization here */
+
+ return stm32_bringup();
+#endif
+}
diff --git a/boards/arm/stm32/stm32f401rc-rs485/src/stm32_autoleds.c b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_autoleds.c
new file mode 100644
index 0000000000..12ad0ba09c
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_autoleds.c
@@ -0,0 +1,81 @@
+/****************************************************************************
+ * boards/arm/stm32/stm32f401rc-rs485/src/stm32_autoleds.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership. The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <debug.h>
+
+#include <nuttx/board.h>
+
+#include "chip.h"
+#include "arm_internal.h"
+#include "stm32.h"
+#include "stm32f401rc-rs485.h"
+
+#include <arch/board/board.h>
+
+#ifdef CONFIG_ARCH_LEDS
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: board_autoled_initialize
+ ****************************************************************************/
+
+void board_autoled_initialize(void)
+{
+ /* Configure LD2 GPIO for output */
+
+ stm32_configgpio(GPIO_LED1);
+}
+
+/****************************************************************************
+ * Name: board_autoled_on
+ ****************************************************************************/
+
+void board_autoled_on(int led)
+{
+ if (led == 1)
+ {
+ stm32_gpiowrite(GPIO_LED1, true);
+ }
+}
+
+/****************************************************************************
+ * Name: board_autoled_off
+ ****************************************************************************/
+
+void board_autoled_off(int led)
+{
+ if (led == 1)
+ {
+ stm32_gpiowrite(GPIO_LED1, false);
+ }
+}
+
+#endif /* CONFIG_ARCH_LEDS */
diff --git a/boards/arm/stm32/stm32f401rc-rs485/src/stm32_boot.c b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_boot.c
new file mode 100644
index 0000000000..bd2179b98d
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_boot.c
@@ -0,0 +1,85 @@
+/****************************************************************************
+ * boards/arm/stm32/stm32f401rc-rs485/src/stm32_boot.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership. The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <debug.h>
+
+#include <nuttx/arch.h>
+
+#include <arch/board/board.h>
+
+#include "arm_internal.h"
+#include "stm32f401rc-rs485.h"
+
+#include <nuttx/board.h>
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_boardinitialize
+ *
+ * Description:
+ * All STM32 architectures must provide the following entry point.
+ * This entry point is called early in the initialization -- after all
+ * memory has been configured and mapped but before any devices have been
+ * initialized.
+ *
+ ****************************************************************************/
+
+void stm32_boardinitialize(void)
+{
+ /* Configure on-board LEDs if LED support has been selected. */
+
+#ifdef CONFIG_ARCH_LEDS
+ board_autoled_initialize();
+#endif
+}
+
+/****************************************************************************
+ * Name: board_late_initialize
+ *
+ * Description:
+ * If CONFIG_BOARD_LATE_INITIALIZE is selected, then an additional
+ * initialization call will be performed in the boot-up sequence to a
+ * function called board_late_initialize(). board_late_initialize() will
+ * be called immediately after up_initialize() is called and just before
+ * the initial application is started. This additional initialization
+ * phase may be used, for example, to initialize board-specific device
+ * drivers.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_BOARD_LATE_INITIALIZE
+void board_late_initialize(void)
+{
+ /* Perform board initialization here instead of from the
+ * board_app_initialize().
+ */
+
+ stm32_bringup();
+}
+#endif
diff --git a/boards/arm/stm32/stm32f401rc-rs485/src/stm32_bringup.c b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_bringup.c
new file mode 100644
index 0000000000..0baef6aae3
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/src/stm32_bringup.c
@@ -0,0 +1,65 @@
+/****************************************************************************
+ * boards/arm/stm32/stm32f401rc-rs485/src/stm32_bringup.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership. The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdio.h>
+#include <syslog.h>
+#include <errno.h>
+
+#include <nuttx/arch.h>
+
+#include <stm32.h>
+#include <stm32_uart.h>
+
+#include <arch/board/board.h>
+
+#include "stm32f401rc-rs485.h"
+
+#include <nuttx/board.h>
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_bringup
+ *
+ * Description:
+ * Perform architecture-specific initialization
+ *
+ * CONFIG_BOARD_LATE_INITIALIZE=y :
+ * Called from board_late_initialize().
+ *
+ * CONFIG_BOARD_LATE_INITIALIZE=n && CONFIG_BOARDCTL=y :
+ * Called from the NSH library
+ *
+ ****************************************************************************/
+
+int stm32_bringup(void)
+{
+ int ret = OK;
+
+ return ret;
+}
diff --git a/boards/arm/stm32/stm32f401rc-rs485/src/stm32f401rc-rs485.h b/boards/arm/stm32/stm32f401rc-rs485/src/stm32f401rc-rs485.h
new file mode 100644
index 0000000000..d720588b08
--- /dev/null
+++ b/boards/arm/stm32/stm32f401rc-rs485/src/stm32f401rc-rs485.h
@@ -0,0 +1,309 @@
+/****************************************************************************
+ * boards/arm/stm32/stm32f401rc-rs485/src/stm32f401rc-rs485.h
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership. The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+#ifndef __BOARDS_ARM_STM32_STM32F401RC_RS485_SRC_STM32F401RC_RS485_H
+#define __BOARDS_ARM_STM32_STM32F401RC_RS485_SRC_STM32F401RC_RS485_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <nuttx/compiler.h>
+
+#include <stdint.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* Configuration ************************************************************/
+
+#define HAVE_MMCSD 1
+#if !defined(CONFIG_STM32_SDIO) || !defined(CONFIG_MMCSD) || \
+ !defined(CONFIG_MMCSD_SDIO)
+# undef HAVE_MMCSD
+#endif
+
+/* LED. User LD2: the green LED is a user LED connected to Arduino signal
+ * D13 corresponding to MCU I/O PA5 (pin 21) or PB13 (pin 34) depending on
+ * the STM32 target.
+ *
+ * - When the I/O is HIGH value, the LED is on.
+ * - When the I/O is LOW, the LED is off.
+ */
+
+#define GPIO_LED1 \
+ (GPIO_PORTC | GPIO_PIN0 | GPIO_OUTPUT_CLEAR | GPIO_OUTPUT | GPIO_PULLUP | \
+ GPIO_SPEED_50MHz)
+
+/* Buttons
+ *
+ * B1 USER: the user button is connected to the I/O PC13 (pin 2) of the STM32
+ * microcontroller.
+ */
+
+#define MIN_IRQBUTTON BUTTON_USER
+#define MAX_IRQBUTTON BUTTON_USER
+#define NUM_IRQBUTTONS 1
+
+#define GPIO_BTN_USER \
+ (GPIO_INPUT |GPIO_FLOAT |GPIO_EXTI | GPIO_PORTC | GPIO_PIN13)
+
+/* The shield uses the following pins:
+ *
+ * +5V
+ * GND
+ * SERIAL_TX=PA_2 USER_BUTTON=PC_13
+ * SERIAL_RX=PA_3 LD2=PA_5
+ *
+ * Analog Digital
+ * A0=PA_0 USART2RX D0=PA_3 D8 =PA_9
+ * A1=PA_1 USART2TX D1=PA_2 D9 =PC_7
+ * A2=PA_4 D2=PA_10 WIFI_CS=D10=PB_6 SPI_CS
+ * A3=PB_0 WIFI_INT=D3=PB_3 D11=PA_7 SPI_MOSI
+ * A4=PC_1 SD_CS=D4=PB_5 D12=PA_6 SPI_MISO
+ * A5=PC_0 WIFI_EN=D5=PB_4 LD2=D13=PA_5 SPI_SCK
+ * LED2=D6=PB_10 I2C1_SDA=D14=PB_9 WIFI Probe
+ * D7=PA_8 I2C1_SCL=D15=PB_8 WIFI Probe
+ *
+ * mostly from: https://mbed.org/platforms/ST-Nucleo-F401RE/
+ *
+ */
+
+/* SPI1 off */
+
+#define GPIO_SPI1_MOSI_OFF (GPIO_INPUT | GPIO_PULLDOWN | \
+ GPIO_PORTA | GPIO_PIN7)
+#define GPIO_SPI1_MISO_OFF (GPIO_INPUT | GPIO_PULLDOWN | \
+ GPIO_PORTA | GPIO_PIN6)
+#define GPIO_SPI1_SCK_OFF (GPIO_INPUT | GPIO_PULLDOWN | \
+ GPIO_PORTA | GPIO_PIN5)
+
+/* SSD1306 */
+
+#define GPIO_SSD1306_CS (GPIO_OUTPUT|GPIO_OTYPER_PP(0)|GPIO_SPEED_2MHz|\
+ GPIO_OUTPUT_SET|GPIO_PORTB|GPIO_PIN6)
+
+#define GPIO_SSD1306_CMD (GPIO_OUTPUT|GPIO_OTYPER_PP(0)|GPIO_OSPEED_2MHz|\
+ GPIO_OUTPUT_SET|GPIO_PORTC|GPIO_PIN7)
+
+#define GPIO_SSD1306_RST (GPIO_OUTPUT|GPIO_OTYPER_PP(0)|GPIO_SPEED_2MHz|\
+ GPIO_OUTPUT_SET|GPIO_PORTA|GPIO_PIN9)
+
+/* MCP2551 */
+
+#define GPIO_MCP2515_CS (GPIO_OUTPUT|GPIO_OTYPER_PP(0)|GPIO_SPEED_2MHz|\
+ GPIO_OUTPUT_SET|GPIO_PORTA|GPIO_PIN4)
+
+#define GPIO_MCP2515_IRQ (GPIO_INPUT|GPIO_FLOAT|GPIO_PORTA|GPIO_PIN1)
+
+#ifdef HAVE_MMCSD
+# define GPIO_SPI_CS_SD_CARD_OFF \
+ (GPIO_INPUT | GPIO_PULLDOWN | GPIO_SPEED_2MHz | \
+ GPIO_PORTB | GPIO_PIN5)
+#endif
+
+#ifdef HAVE_MMCSD
+# define GPIO_SPI_CS_SD_CARD \
+ (GPIO_OUTPUT | GPIO_PUSHPULL | GPIO_SPEED_2MHz | \
+ GPIO_OUTPUT_SET | GPIO_PORTB | GPIO_PIN5)
+#endif
+
+/* Devices on the onboard bus.
+ *
+ * Note that these are unshifted addresses.
+ */
+
+#define NUCLEO_I2C_OBDEV_LED 0x55
+#define NUCLEO_I2C_OBDEV_HMC5883 0x1e
+
+/* Itead Joystick Shield
+ *
+ * See http://imall.iteadstudio.com/im120417014.html for more information
+ * about this joystick.
+ *
+ * --------- ----------------- ---------------------------------
+ * ARDUINO ITEAD NUCLEO-F4x1
+ * PIN NAME SIGNAL SIGNAL
+ * --------- ----------------- ---------------------------------
+ * D3 Button E Output PB3
+ * D4 Button D Output PB5
+ * D5 Button C Output PB4
+ * D6 Button B Output PB10
+ * D7 Button A Output PA8
+ * D8 Button F Output PA9
+ * D9 Button G Output PC7
+ * A0 Joystick Y Output PA0 ADC1_0
+ * A1 Joystick X Output PA1 ADC1_1
+ * --------- ----------------- ---------------------------------
+ *
+ * All buttons are pulled on the shield. A sensed low value indicates
+ * when the button is pressed.
+ *
+ * NOTE: Button F cannot be used with the default USART1 configuration
+ * because PA9 is configured for USART1_RX by default. Use select
+ * different USART1 pins in the board.h file or select a different
+ * USART or select CONFIG_NUCLEO_F401RE_AJOY_MINBUTTONS which will
+ * eliminate all but buttons A, B, and C.
+ */
+
+#define ADC_XOUPUT 1 /* X output is on ADC channel 1 */
+#define ADC_YOUPUT 0 /* Y output is on ADC channel 0 */
+
+#define GPIO_BUTTON_A \
+ (GPIO_INPUT | GPIO_PULLUP |GPIO_EXTI | GPIO_PORTA | GPIO_PIN8)
+#define GPIO_BUTTON_B \
+ (GPIO_INPUT | GPIO_PULLUP |GPIO_EXTI | GPIO_PORTB | GPIO_PIN10)
+#define GPIO_BUTTON_C \
+ (GPIO_INPUT | GPIO_PULLUP |GPIO_EXTI | GPIO_PORTB | GPIO_PIN4)
+#define GPIO_BUTTON_D \
+ (GPIO_INPUT | GPIO_PULLUP |GPIO_EXTI | GPIO_PORTB | GPIO_PIN5)
+#define GPIO_BUTTON_E \
+ (GPIO_INPUT | GPIO_PULLUP |GPIO_EXTI | GPIO_PORTB | GPIO_PIN3)
+#define GPIO_BUTTON_F \
+ (GPIO_INPUT | GPIO_PULLUP |GPIO_EXTI | GPIO_PORTA | GPIO_PIN9)
+#define GPIO_BUTTON_G \
+ (GPIO_INPUT | GPIO_PULLUP |GPIO_EXTI | GPIO_PORTC | GPIO_PIN7)
+
+/* Itead Joystick Signal interpretation:
+ *
+ * --------- ----------------------- ---------------------------
+ * BUTTON TYPE NUTTX ALIAS
+ * --------- ----------------------- ---------------------------
+ * Button A Large button A JUMP/BUTTON 3
+ * Button B Large button B FIRE/BUTTON 2
+ * Button C Joystick select button SELECT/BUTTON 1
+ * Button D Tiny Button D BUTTON 6
+ * Button E Tiny Button E BUTTON 7
+ * Button F Large Button F BUTTON 4
+ * Button G Large Button G BUTTON 5
+ * --------- ----------------------- ---------------------------
+ */
+
+#define GPIO_BUTTON_1 GPIO_BUTTON_C
+#define GPIO_BUTTON_2 GPIO_BUTTON_B
+#define GPIO_BUTTON_3 GPIO_BUTTON_A
+#define GPIO_BUTTON_4 GPIO_BUTTON_F
+#define GPIO_BUTTON_5 GPIO_BUTTON_G
+#define GPIO_BUTTON_6 GPIO_BUTTON_D
+#define GPIO_BUTTON_7 GPIO_BUTTON_E
+
+#define GPIO_SELECT GPIO_BUTTON_1
+#define GPIO_FIRE GPIO_BUTTON_2
+#define GPIO_JUMP GPIO_BUTTON_3
+
+/****************************************************************************
+ * Public Data
+ ****************************************************************************/
+
+/* Global driver instances */
+
+#ifdef CONFIG_STM32_SPI1
+extern struct spi_dev_s *g_spi1;
+#endif
+#ifdef CONFIG_STM32_SPI2
+extern struct spi_dev_s *g_spi2;
+#endif
+#ifdef HAVE_MMCSD
+extern struct sdio_dev_s *g_sdio;
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: stm32_bringup
+ *
+ * Description:
+ * Perform architecture specific initialization
+ *
+ * CONFIG_BOARDCTL=y:
+ * If CONFIG_NSH_ARCHINITIALIZE=y:
+ * Called from the NSH library (or other application)
+ * Otherwise, assumed to be called from some other application.
+ *
+ * Otherwise CONFIG_BOARD_LATE_INITIALIZE=y:
+ * Called from board_late_initialize().
+ *
+ * Otherwise, bad news: Never called
+ *
+ ****************************************************************************/
+
+int stm32_bringup(void);
+
+/****************************************************************************
+ * Name: stm32_spidev_initialize
+ *
+ * Description:
+ * Called to configure SPI chip select GPIO pins.
+ *
+ ****************************************************************************/
+
+void stm32_spidev_initialize(void);
+
+/****************************************************************************
+ * Name: stm32_usbinitialize
+ *
+ * Description:
+ * Called to setup USB-related GPIO pins.
+ *
+ ****************************************************************************/
+
+void stm32_usbinitialize(void);
+
+/****************************************************************************
+ * Name: stm32_adc_setup
+ *
+ * Description:
+ * Initialize ADC and register the ADC driver.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_ADC
+int stm32_adc_setup(void);
+#endif
+
+/****************************************************************************
+ * Name: board_ajoy_initialize
+ *
+ * Description:
+ * Initialize and register the button joystick driver
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_INPUT_AJOYSTICK
+int board_ajoy_initialize(void);
+#endif
+
+/****************************************************************************
+ * Name: stm32_mcp2515initialize
+ *
+ * Description:
+ * Initialize and register the MCP2515 CAN driver.
+ *
+ ****************************************************************************/
+
+#ifdef CONFIG_CAN_MCP2515
+int stm32_mcp2515initialize(const char *devpath);
+#endif
+
+#endif /* __BOARDS_ARM_STM32_STM32F401RC_RS485_SRC_STM32F401RC_RS485_H */