assembly

HI
After exucating this two program code
AREA armtxt,CODE,READONLY ENTRY MOV R0,#0x0F MOV R1,#0x0F MOV R2,#0x0F MOV R3,#0x0F MOV R4,#0x0F END

AREA armtxt,CODE,READONLY ENTRY
Main MOV R0,#0x0F MOV R1,#0x0F MOV R2,#0x0F MOV R3,#0x0F MOV R4,#0x0F END

i am geting this error what is wrong with code

Build target 'Target 1'
assembling Startup.s...
linking...
sd.axf: Warning: L6665W: Neither Lib$$Request$$armlib Lib$$Request$$cpplib defined, not searching ARM libraries.
sd.axf: Error: L6411W: No compatible library exists with a definition of startup symbol __main.
Target not createderror