I attempted to add spi_master as below, but I am in trouble with link error. If anyone knows the cause, please tell me.
*** Using Compiler 'V5.06 update 4 (build 422)', folder: 'C:\Keil_v5\ARM\ARMCC\Bin'
Build target 'nrf52832_xxaa'
linking...
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol sd_nvic_ClearPendingIRQ (referred from spi_master.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol sd_nvic_DisableIRQ (referred from spi_master.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol sd_nvic_EnableIRQ (referred from spi_master.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol sd_nvic_SetPriority (referred from spi_master.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol sd_nvic_critical_region_enter (referred from spi_master.o).
.\_build\nrf52832_xxaa.axf: Error: L6218E: Undefined symbol sd_nvic_critical_region_exit (referred from spi_master.o).
Not enough information to list image symbols.
Finished: 1 information, 0 warning and 6 error messages.
".\_build\nrf52832_xxaa.axf" - 6 Error(s), 0 Warning(s).
Target not created.
Build Time Elapsed: 00:00:01
