Android Question negative value in the received data

You can convert signed bytes (-128 to +127) to unsigned (0 to 255) using bitwise And eg:


If you take the variable that contains -64 (could be 8-bit Byte 0xC0, or 16-bit Short 0xFFC0, or 32-bit Int 0xFFFFFFC0) and do a Bit.And(variable, 0xFF) on it, it will return just the lower 8 bits 0x000000C0 ie 0xC0 ie 192.

emexes said:

You can convert signed bytes (-128 to +127) to unsigned (0 to 255) using bitwise And eg:

B4X:

For I = 0 to 255 step 15
    Dim B As Byte = I
    Dim UnsignedValue As Int = Bit.And(B, 0xFF)    'converts signed Byte value to unsigned
    Log(I & Tab & B & Tab & UnsignedValue)
Next

If you take the variable that contains -64 (could be 8-bit Byte 0xC0, or 16-bit Short 0xFFC0, or 32-bit Int 0xFFFFFFC0) and do a Bit.And(variable, 0xFF) on it, it will return just the lower 8 bits 0x000000C0 ie 0xC0 ie 192.

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Thank you very much!!
I'm still learning and there's so much I don't know yet.
I wish you all the best!!

Picon said:

learning

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Modifed code in post #2 so that it includes your -64, and added Log output. ?

emexes said:

Modifed code in post #2 so that it includes your -64, and added Log output. ?

Click to expand...

Brooklyn Lager ??