方案一:Arduino esp32
經過一番折騰，終於運行了。
參考：Arduino
方案二：esp-idf
分支一:使用esp官方spi庫
報錯
` > Executing task: cmake --build . <
[1/5] Performing build step for 'bootloader'
ninja: no work to do.
[2/3] Linking CXX executable spi_master.elf
FAILED: spi_master.elf省略
-elf/8.4.0/../../../../xtensa-esp32s2-elf/bin/ld: esp-idf/freertos/libfreertos.a(port_common.c.obj)😦.literal.main_task+0x10): undefined reference to 'app_main'
/Users/workspace/.espressif/tools/xtensa-esp32s2-elf/esp-2020r3-8.4.0/xtensa-esp32s2-elf/bin/../lib/gcc/xtensa-esp32s2-elf/8.4.0/../../../../xtensa-esp32s2-elf/bin/ld: esp-idf/freertos/libfreertos.a(port_common.c.obj): in function 'main_task':
/Users/workspace/esp/esp-idf/components/freertos/port/port_common.c:122: undefined reference to 'app_main'
collect2: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.
終端進程已終止，退出代碼: 1
For the ESP-IDF framework, the main() function needs to be named app_main()
查了esp官方文檔，需要main文件夾及component文件，參考官方example
分支二：軟件模擬spi
spi要用到的管腳:cs,dc,scl,sda
把uint8_t拆分成8個位，分別對管腳使能0/1
偽代碼for(i=0;i<8;i++) //傳送8bit數據 { if(dat&0x80) SDIN = 1;} else {SDIN = 0;} SCLK = 0; dat = dat << 1; SCLK = 1;