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8-bit signed?

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SaladFingersCreated:
SaladFingers#1
Is it possible to convert an integer to an 8bit signed integer? Edit: I guess I wasn’t trying hard enough, my integer was already 1 byte long, just needed to get rid of the most significant bit. Edit 2: I was wrong, I still need some help. I have a number, for example &B11111011 (251) and I need it to be represented as a negative, signed number.
12Me21#2
For converting a signed number to a larger integer type (8 bit -> 32 bit) you can use the fact that >> preserves the highest bit: 
X<<(32-8)>>(32-8)
for example, 
&B11111011
<<24
&B11111011000000000000000000000000
>>24
&B11111111111111111111111111111011 (-5)
hanzo#3
It is possible if the integer is in the range of -128 to 127. Could you refer to the following program? 
ACLS
A%=256
WHILE A%<-128 || A%>127
 INPUT"AN INTEGER (-128 TO 127)";A%
WEND

B%=A%+256*(A%<0)

?"8BIT SIGNED INT OF ";:?A%
?" = ";:?"&B";:?BIN$(B%,8);
?"(&H";:?HEX$(B%,2);:?")"
hanzo#4
I'm sorry I've lost your EDIT2 but it is very simple as follows. 
A%=&B11111011
?A%-256*(A%>=128)