libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `set_ym_clock'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `set_bus_ctl'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `set_data_out'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `set_data_in'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `set_address'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `set_data'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `get_data'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `send_data'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
libraries/YM2149/ym2149.c.o (symbol from plugin): In function `set_ym_clock':
(.text+0x0): multiple definition of `read_data'
sketch/ym2149.c.o (symbol from plugin).text+0x0): first defined here
/var/folders/xv/p4nlbyh12w3dfympc6_5pj_80000gn/T//cc6JF2Pd.ltrans0.ltrans.o: In function `setup':
/Users/starock/Desktop/YM2149/YM2149.ino:38: undefined reference to `set_ym_clock()'
/Users/starock/Desktop/YM2149/YM2149.ino:39: undefined reference to `set_bus_ctl()'
collect2: error: ld returned 1 exit status
exit status 1
Error compiling for board Arduino/Genuino Uno.