最近在捣鼓LimeSDR,如果只使用USB供电的话，默认USB固件只向系统声明了400MA的电流。
明显当设备全功率运行的话，是不够设备使用的，全功率大约是3W以上的样子，因此，我们需要调整USB固件，向系统多申请些电流。
USB 3.0可以提供900MA的电流。
下面是如何编译LimeSDR的USB固件:
$ cd ~ $ wget http://www.mobibrw.com/wp-content/uploads/2018/02/FX3_SDK_Linux_v1.3.3.tar.gz $ tar -zxvf FX3_SDK_Linux_v1.3.3.tar.gz $ tar -zxvf ARM_GCC.tar.gz $ tar -zxvf fx3_firmware_linux.tar.gz $ tar -zxvf eclipse_x64.tar.gz $ export PATH=~/arm-2013.11/bin:$PATH $ export FX3_INSTALL_PATH=~/cyfx3sdk $ export ARMGCC_INSTALL_PATH=~/arm-2013.11 $ export ARMGCC_VERSION=4.8.1 #编译镜像打包工具 $ cd ~/cyfx3sdk/util/elf2img $ gcc elf2img.c -o elf2img -Wall $ cd ~ $ git clone https://github.com/myriadrf/LimeSDR-USB_FX3.git $ ./eclipse/ezUsbSuite
参照下面的步骤导入工程（但是要注意的是，用ezUsbSuite开发，目前在不修改工程的情况下，只能在Windows下开发，原因是模板设置的时候，部分路径没有配置正确)
对于ubuntu系统,并且需要使用命令行编译的情况，需要手工生成如下几个文件( 这几个文件根据Debug目录下的配置文件修改来的）
$ cd LimeSDR-USB_FX3 $ mkdir Release $ cd Release $ touch makefile $ touch objects.mk $ touch sources.mk $ touch subdir.mk
编译配置文件的内容如下：
makefile
################################################################################ # Automatically-generated file. Do not edit! ################################################################################ RM := rm -rf # All of the sources participating in the build are defined here -include sources.mk -include subdir.mk -include objects.mk ifneq ($(MAKECMDGOALS),clean) ifneq ($(strip $(ASM_DEPS)),) -include $(ASM_DEPS) endif ifneq ($(strip $(S_UPPER_DEPS)),) -include $(S_UPPER_DEPS) endif ifneq ($(strip $(C_DEPS)),) -include $(C_DEPS) endif endif -include ../makefile.defs # Add inputs and outputs from these tool invocations to the build variables SECONDARY_LIST += \ LimeSDR-USB_FX3.lst \ SECONDARY_SIZE += \ LimeSDR-USB_FX3.siz \ # All Target all: LimeSDR-USB_FX3.elf secondary-outputs # Tool invocations LimeSDR-USB_FX3.elf: $(OBJS) $(USER_OBJS) @echo 'Building target: $@' @echo 'Invoking: ARM Sourcery Windows GCC C Linker' arm-none-eabi-gcc $(OBJS) $(USER_OBJS) $(LIBS) -T"$(FX3_INSTALL_PATH)/firmware/common/fx3.ld" -nostartfiles -Wl,-Map,LimeSDR-USB_FX3.map -Wl,-d -Wl,--no-wchar-size-warning -Wl,--entry,CyU3PFirmwareEntry "$(FX3_INSTALL_PATH)/firmware/u3p_firmware/lib/fx3_release/cyfxapi.a" "$(FX3_INSTALL_PATH)/firmware/u3p_firmware/lib/fx3_release/cyu3lpp.a" "$(FX3_INSTALL_PATH)/firmware/u3p_firmware/lib/fx3_release/cyu3threadx.a" "$(ARMGCC_INSTALL_PATH)/arm-none-eabi/lib/libc.a" "$(ARMGCC_INSTALL_PATH)/lib/gcc/arm-none-eabi/4.8.1/libgcc.a" -mcpu=arm926ej-s -mthumb-interwork -o"LimeSDR-USB_FX3.elf" @echo 'Finished building target: $@' @echo ' ' $(MAKE) --no-print-directory post-build LimeSDR-USB_FX3.lst: LimeSDR-USB_FX3.elf @echo 'Invoking: ARM Sourcery Windows GNU Create Listing' arm-none-eabi-objdump -h -S LimeSDR-USB_FX3.elf > "LimeSDR-USB_FX3.lst" @echo 'Finished building: $@' @echo ' ' LimeSDR-USB_FX3.siz: LimeSDR-USB_FX3.elf @echo 'Invoking: ARM Sourcery Windows GNU Print Size' arm-none-eabi-size --format=berkeley LimeSDR-USB_FX3.elf @echo 'Finished building: $@' @echo ' ' # Other Targets clean: -$(RM) $(EXECUTABLES)$(OBJS)$(SECONDARY_LIST)$(SECONDARY_SIZE)$(ASM_DEPS)$(S_UPPER_DEPS)$(C_DEPS) LimeSDR-USB_FX3.elf -@echo ' ' post-build: -@echo 'Converting ELF to image (.img) format' -"$(FX3_INSTALL_PATH)/util/elf2img/elf2img" -i LimeSDR-USB_FX3.elf -o LimeSDR-USB_FX3.img -@echo ' ' secondary-outputs: $(SECONDARY_LIST) $(SECONDARY_SIZE) .PHONY: all clean dependents .SECONDARY: post-build -include ../makefile.targets
objects.mk
################################################################################ # Automatically-generated file. Do not edit! ################################################################################ USER_OBJS := LIBS :=
sources.mk
################################################################################ # Automatically-generated file. Do not edit! ################################################################################ ELF_SRCS := OBJ_SRCS := ASM_SRCS := C_SRCS := S_UPPER_SRCS := O_SRCS := EXECUTABLES := OBJS := SECONDARY_LIST := SECONDARY_SIZE := ASM_DEPS := S_UPPER_DEPS := C_DEPS := # Every subdirectory with source files must be described here SUBDIRS := \ . \
subdir.mk
################################################################################ # Automatically-generated file. Do not edit! ################################################################################ # Add inputs and outputs from these tool invocations to the build variables C_SRCS += \ ../main.c \ ../rtos_threadx.c \ ../spi_flash_lib.c \ ../usb_descriptors.c S_UPPER_SRCS += \ ../cyfx_gcc_startup.S OBJS += \ ./cyfx_gcc_startup.o \ ./main.o \ ./rtos_threadx.o \ ./spi_flash_lib.o \ ./usb_descriptors.o S_UPPER_DEPS += \ ./cyfx_gcc_startup.d C_DEPS += \ ./main.d \ ./rtos_threadx.d \ ./spi_flash_lib.d \ ./usb_descriptors.d # Each subdirectory must supply rules for building sources it contributes %.o: ../%.S @echo 'Building file: $<' @echo 'Invoking: ARM Sourcery Windows GCC Assembler' arm-none-eabi-gcc -x assembler-with-cpp -I"$(FX3_INSTALL_PATH)/firmware/u3p_firmware/inc" -Wall -Wa,-adhlns="$@.lst" -c -fmessage-length=0 -MMD -MP -MF"$(@:%.o=%.d)" -MT"$(@:%.o=%.d)" -mcpu=arm926ej-s -mthumb-interwork -o "$@" "$<" @echo 'Finished building: $<' @echo ' ' %.o: ../%.c @echo 'Building file: $<' @echo 'Invoking: ARM Sourcery Windows GCC C Compiler' arm-none-eabi-gcc -D__CYU3P_TX__=1 -I"$(FX3_INSTALL_PATH)/firmware/u3p_firmware/inc" -I"..\." -Os -Wall -Wa,-adhlns="$@.lst" -c -fmessage-length=0 -MMD -MP -MF"$(@:%.o=%.d)" -MT"$(@:%.o=%.d)" -mcpu=arm926ej-s -mthumb-interwork -o "$@" "$<" @echo 'Finished building: $<' @echo ' '
上面的文件生成后，在同一个Shell中执行
#编译之前确保 FX3_INSTALL_PATH，ARMGCC_INSTALL_PATH等几个环境变量已经正确定义 $ make clean $ make
即可在Release目录下生成LimeSDR-USB_FX3.img，这个就是需要的刷机镜像。
参照ubuntu 16.04修复固件刷新失败的LimeSDR-USB V1.4，或者
$ LimeUtil --fw="LimeSDR-USB_FX3.img"
刷新固件即可。
至于电源控制部分的代码，调整usb_descriptors.c里面的Max power部分的数字即可：
/* Standard super speed configuration descriptor */
const uint8_t CyFxUSBSSConfigDscr[] __attribute__ ((aligned (32))) =
{
/* Configuration descriptor */
0x09, /* Descriptor size */
CY_U3P_USB_CONFIG_DESCR, /* Configuration descriptor type */
0x46,0x00, /* Length of this descriptor and all sub descriptors */
0x01, /* Number of interfaces */
0x01, /* Configuration number */
0x00, /* COnfiguration string index */
0x80, /* Config characteristics - Bus powered */
0x32, /* Max power consumption of device (in 8mA unit) : 400mA */
刷新完成后，使用
#注意，ubuntu 16.04版本的lsusb -v ，命令显示的 MaxPower 参数是不正确的 $ usb-devices
查看设备供电情况。
如果固件代码无法成功下载，可以本站下载一份拷贝。