5.4. Building the Connext DDS Micro Source for FreeRTOS¶
5.4.1. Introduction¶
This section explains the environment used to run Connext DDS Micro on FreeRTOS + lwIP and is organized as follows:
5.4.2. Overview¶
Connext DDS Micro is known to run on the FreeRTOS operating system with the lwIP protocol stack. STM32F769I-DISC0 has been chosen as reference hardware. This development kit has a STM32F769NIH6 microcontroller with 2 Mbytes of Flash memory and 512 Kbytes of RAM. For a full description, please refer to the microcontroller documentation.
STM provides a toolchain called SW4STM32. SW4STM32 is a free multi-OS software environment based on Eclipse, which supports the full range of STM32 microcontrollers and associated boards. SW4STM32 includes the GCC C/C++ compiler, a GDB-based debugger, and an Eclipse-based IDE.
STM also provides STM32CubeF7. STM32CubeF7 gathers all the generic embedded software components required to develop an application on the STM32F7 microcontrollers in a single package.
STM32CubeF7 also includes many examples and demonstration applications. The example LwIP_HTTP_Server_Socket_RTOS is particularly useful as it provides a working FreeRTOS + lwIP configuration.
The following versions of the different components have been used:
SW4STM32 version 2.1
STM32Cube_FW_F7 version V1.7.0
FreeRTOS version V9.0.0
lwIP version V2.0.0
5.4.3. Configuration¶
Example lwIP and FreeRTOS configurations are provided below for reference. This configuration must be tuned according to your needs. Details about how to configure these third-party components can be found in the FreeRTOS and lwIP documentation.
Example configuration for lwIP:
#ifndef __LWIPOPTS_H__
#define __LWIPOPTS_H__
#include <limits.h>
#define NO_SYS 0
/* ---------- Memory options ---------- */
#define MEM_ALIGNMENT 4
#define MEM_SIZE (50*1024)
#define MEMP_NUM_PBUF 10
#define MEMP_NUM_UDP_PCB 6
#define MEMP_NUM_TCP_PCB 10
#define MEMP_NUM_TCP_PCB_LISTEN 5
#define MEMP_NUM_TCP_SEG 8
#define MEMP_NUM_SYS_TIMEOUT 10
/* ---------- Pbuf options ---------- */
#define PBUF_POOL_SIZE 8
#define PBUF_POOL_BUFSIZE 1524
/* ---------- IPv4 options ---------- */
#define LWIP_IPV4 1
/* ---------- TCP options ---------- */
#define LWIP_TCP 1
#define TCP_TTL 255
#define TCP_QUEUE_OOSEQ 0
#define TCP_MSS (1500 - 40) /* TCP_MSS = (Ethernet MTU - IP header size - TCP header size) */
#define TCP_SND_BUF (4*TCP_MSS)
#define TCP_SND_QUEUELEN (2* TCP_SND_BUF/TCP_MSS)
#define TCP_WND (2*TCP_MSS)
/* ---------- ICMP options ---------- */
#define LWIP_ICMP 1
/* ---------- DHCP options ---------- */
#define LWIP_DHCP 1
/* ---------- UDP options ---------- */
#define LWIP_UDP 1
#define UDP_TTL 255
/* ---------- Statistics options ---------- */
#define LWIP_STATS 0
/* ---------- link callback options ---------- */
#define LWIP_NETIF_LINK_CALLBACK 1
/*
--------------------------------------
---------- Checksum options ----------
--------------------------------------
*/
/*
The STM32F7xx allows computing and verifying checksums by hardware
*/
#define CHECKSUM_BY_HARDWARE
#ifdef CHECKSUM_BY_HARDWARE
/* CHECKSUM_GEN_IP==0: Generate checksums by hardware for outgoing IP packets.*/
#define CHECKSUM_GEN_IP 0
/* CHECKSUM_GEN_UDP==0: Generate checksums by hardware for outgoing UDP packets.*/
#define CHECKSUM_GEN_UDP 0
/* CHECKSUM_GEN_TCP==0: Generate checksums by hardware for outgoing TCP packets.*/
#define CHECKSUM_GEN_TCP 0
/* CHECKSUM_CHECK_IP==0: Check checksums by hardware for incoming IP packets.*/
#define CHECKSUM_CHECK_IP 0
/* CHECKSUM_CHECK_UDP==0: Check checksums by hardware for incoming UDP packets.*/
#define CHECKSUM_CHECK_UDP 0
/* CHECKSUM_CHECK_TCP==0: Check checksums by hardware for incoming TCP packets.*/
#define CHECKSUM_CHECK_TCP 0
/* CHECKSUM_CHECK_ICMP==0: Check checksums by hardware for incoming ICMP packets.*/
#define CHECKSUM_GEN_ICMP 0
#else
/* CHECKSUM_GEN_IP==1: Generate checksums in software for outgoing IP packets.*/
#define CHECKSUM_GEN_IP 1
/* CHECKSUM_GEN_UDP==1: Generate checksums in software for outgoing UDP packets.*/
#define CHECKSUM_GEN_UDP 1
/* CHECKSUM_GEN_TCP==1: Generate checksums in software for outgoing TCP packets.*/
#define CHECKSUM_GEN_TCP 1
/* CHECKSUM_CHECK_IP==1: Check checksums in software for incoming IP packets.*/
#define CHECKSUM_CHECK_IP 1
/* CHECKSUM_CHECK_UDP==1: Check checksums in software for incoming UDP packets.*/
#define CHECKSUM_CHECK_UDP 1
/* CHECKSUM_CHECK_TCP==1: Check checksums in software for incoming TCP packets.*/
#define CHECKSUM_CHECK_TCP 1
/* CHECKSUM_CHECK_ICMP==1: Check checksums by hardware for incoming ICMP packets.*/
#define CHECKSUM_GEN_ICMP 1
#endif
/*
----------------------------------------------
---------- Sequential layer options ----------
----------------------------------------------
*/
#define LWIP_NETCONN 1
/*
------------------------------------
---------- Socket options ----------
------------------------------------
*/
#define LWIP_SOCKET 1
/*
---------------------------------
---------- OS options ----------
---------------------------------
*/
#define TCPIP_THREAD_NAME "TCP/IP"
#define TCPIP_THREAD_STACKSIZE 1000
#define TCPIP_MBOX_SIZE 6
#define DEFAULT_UDP_RECVMBOX_SIZE 2000
#define DEFAULT_TCP_RECVMBOX_SIZE 2000
#define DEFAULT_ACCEPTMBOX_SIZE 2000
#define DEFAULT_THREAD_STACKSIZE 500
#define TCPIP_THREAD_PRIO osPriorityHigh
/**
* LWIP_SO_RCVBUF==1: Enable SO_RCVBUF processing.
*/
#define LWIP_SO_RCVBUF 1
/**
* Instruct lwIP to use the errno provided by libc instead of the errno in lwIP.
* If your libc doesn't include errno, you might need to delete these macros.
*/
#undef LWIP_PROVIDE_ERRNO
#define LWIP_ERRNO_INCLUDE "errno.h"
#endif /* __LWIPOPTS_H__ */
Example configuration for FreeRTOS:
#ifndef FREERTOS_CONFIG_H
#define FREERTOS_CONFIG_H
/*-----------------------------------------------------------
* Application specific definitions.
*
* These definitions should be adjusted for your application requirements.
*
* THESE PARAMETERS ARE DESCRIBED WITHIN THE 'CONFIGURATION' SECTION OF THE
* FreeRTOS API DOCUMENTATION AVAILABLE ON THE FreeRTOS.org WEB SITE.
*
* See http://www.freertos.org/a00110.html.
*----------------------------------------------------------*/
/* Ensure stdint is only used by the compiler, and not the assembler. */
#if defined(__ICCARM__) || defined(__CC_ARM) || defined(__GNUC__)
#include <stdint.h>
extern uint32_t SystemCoreClock;
#endif
#define configUSE_PREEMPTION 1
#define configUSE_IDLE_HOOK 0
#define configUSE_TICK_HOOK 0
#define configCPU_CLOCK_HZ (SystemCoreClock)
#define configTICK_RATE_HZ ((TickType_t)1000)
#define configMAX_PRIORITIES (7)
#define configMINIMAL_STACK_SIZE ((uint16_t)128)
#define configTOTAL_HEAP_SIZE ((size_t)(400 * 1024))
#define configMAX_TASK_NAME_LEN (16)
#define configUSE_TRACE_FACILITY 1
#define configUSE_16_BIT_TICKS 0
#define configIDLE_SHOULD_YIELD 1
#define configUSE_MUTEXES 1
#define configQUEUE_REGISTRY_SIZE 8
#define configCHECK_FOR_STACK_OVERFLOW 0
#define configUSE_RECURSIVE_MUTEXES 1
#define configUSE_MALLOC_FAILED_HOOK 0
#define configUSE_APPLICATION_TASK_TAG 0
#define configUSE_COUNTING_SEMAPHORES 1
#define configGENERATE_RUN_TIME_STATS 0
/* Co-routine definitions. */
#define configUSE_CO_ROUTINES 0
#define configMAX_CO_ROUTINE_PRIORITIES (2)
/* Software timer definitions. */
#define configUSE_TIMERS 1
#define configTIMER_TASK_PRIORITY (2)
#define configTIMER_QUEUE_LENGTH 10
#define configTIMER_TASK_STACK_DEPTH 1280
/* Set the following definitions to 1 to include the API function, or zero
to exclude the API function. */
#define INCLUDE_vTaskPrioritySet 1
#define INCLUDE_uxTaskPriorityGet 1
#define INCLUDE_vTaskDelete 1
#define INCLUDE_vTaskCleanUpResources 0
#define INCLUDE_vTaskSuspend 1
#define INCLUDE_vTaskDelayUntil 0
#define INCLUDE_vTaskDelay 1
#define INCLUDE_xTaskGetSchedulerState 1
/* Cortex-M specific definitions. */
#ifdef __NVIC_PRIO_BITS
/* __BVIC_PRIO_BITS will be specified when CMSIS is being used. */
#define configPRIO_BITS __NVIC_PRIO_BITS
#else
#define configPRIO_BITS 4 /* 15 priority levels */
#endif
#define configLIBRARY_LOWEST_INTERRUPT_PRIORITY 0xf
#define configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY 5
#define configKERNEL_INTERRUPT_PRIORITY ( configLIBRARY_LOWEST_INTERRUPT_PRIORITY << (8 - configPRIO_BITS) )
#define configMAX_SYSCALL_INTERRUPT_PRIORITY ( configLIBRARY_MAX_SYSCALL_INTERRUPT_PRIORITY << (8 - configPRIO_BITS) )
#define configASSERT( x ) if( ( x ) == 0 ) { taskDISABLE_INTERRUPTS(); for( ;; ); }
#define vPortSVCHandler SVC_Handler
#define xPortPendSVHandler PendSV_Handler
#endif /* FREERTOS_CONFIG_H */
5.4.4. CMake Support¶
Connext DDS Micro includes support to compile libraries for FreeRTOS using CMake . It is assumed that the Connext DDS Micro source-bundle has been downloaded and installed and that CMake is available.
Make sure CMake is in the path.
Define the following environment variables:
CONFIG_PATH : Path where the FreeRTOSConfig.h and lwipopts.h files are located.
FREERTOS_PATH : Path to FreeRTOS source code and header files.
LWIP_PATH : Path to lwIP source code and header files.
PATH : Update your path with the location of the C and C++ compiler. By default arm-none-eabi-gcc and arm-none-eabi-g++ are used as C and C++ compilers.
Enter the following command:
cd <rti_me install directory> resource/scripts/rtime-make --target FreeRTOS --name cortexm7FreeRTOS9.0gcc7.3.1 -G "Unix Makefiles" --build
The Connext DDS Micro libraries are available in:
<rti_me install directory>/lib/cortexm7FreeRTOS9.0gcc7.3.1
NOTE: rtime-make uses the name specified with –name to determine a few settings needed by Connext DDS Micro. Please refer to Preparing for a Build for details.