How to get big number

[Kabin]

I would like to implement my own wallet applet. And I want to credit 1512 , so I sent APDU

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CLA   INS   P1    P2    lC     DATA
80      50   00    00    02     05E8

when I use apdu.getBuffer(); to get this data, the value changes. 0xE8 is supposed to be 232, but because it supports unsigned nature, it shows a different value. What can I do to get 232 in short variable for 0xE8? Thanks for any reply.

[chico0609]

When you have a byte that is greater than 0x7F and meanwhile you want to make it an unsigned value, you can use the following to prevent the sign extension:

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short a = (short) (b & 0xFF);

[UNKNwYSHSA]

Use method makeShort(byte b1, byte b2) in package javacard.framework.Util.
short sv = Util.makeShort( (byte) 0x00, (byte) 0xE8);

[Kabin]

Thank you for all the help. My problem is solved. But I still have one small question. I will new another topic for easy to communicate. Thanks