assembly - why the assembler does not report error on this? -

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consider following 2 statements out of simple assembly language program:

data1 db  +200 data2 db  -130

when try assemble it, assembler gives error on no 2 statement, should since byte can hold beyond -128 decimal. why assembler didn't give error on no 1 statement? afterall, byte can hold max 127 positive signed integer.. instead assemlber put value c8 in byte.

any number converted array of bits when assembled executable. -1, example, 0xff, -2 0xfe, etc. difference between -1 , 255 how used in code. assembler doesn't care, wants store data use.


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