STM32F407+LWIP

1. About using peripheral library and chip selection

Need to define USE_STDPERIPH_DRIVER and STM32F40_41xxx

Specifically defined in stm32f4xx.h or configured in Target Options

2. About clock configuration

This project uses an external crystal oscillator of 8M

Therefore, it is necessary to modify the external crystal oscillator and PLL related macro definitions

Configuration in stm32f4xx.h

#define HSE_VALUE ((uint32_t)8000000)

Configuration in system_stm32f4xx.c

#define PLL_M 8

3. Porting lwip, no RTOS

The first step is to initialize ETH_MAC_DMA and PHY chip. Here we test it in project f407_eth.

Step 2: Add lwip file

The src file contains the files in the lwip official library:

lwip-1.4.1\src

The port contains the official ST transplant file:

STM32F4x7_ETH_LwIP_V1.1.1\Utilities\Third_Party\lwip-1.4.1\port\STM32F4x7

Migrate network application files:

STM32F4x7_ETH_LwIP_V1.1.1\Project\Standalone\udp_echo_client

Step 3: Modify some files

main.h is changed to 

                            net_config.h configures IP/MAC/NETMASK/GW/DHCP, etc. DHCP is not used here

When there is no operating system, you need to initialize systick to use lwip as the time base. Initialize it in the main function and implement SysTick_Handler

ethernetif.c is the file that needs to be ported when there is no RTOS (st has already done it), which is actually initialization, sending, receiving