How do I start at a different index point in a DAT data section?

Don M

Let's say I have this in the DAT section:

data_out      byte $32, $2e, $30, $30, $2c, $52, $30, $30, $43, $30, $30, $2c, $4d, $41, $43, $3a       
              byte $30, $30, $30, $37, $38, $30, $37, $46, $41, $38, $44, $33, $00, $00, $00, $00

I'm playing with the AES object and it only encrypts 16 bytes at a time. I want to encrypt the second 16 bytes so how do I index data_out to do the second set of 16 bytes? The data _out is always going to be 32 bytes long.

The command from the AES object is like this:

aes.ECBEncrypt (@data_out, @ciphertext) 

Thanks.
Don

Phil Pilgrim (PhiPi)

aes.ECBEncrypt (@data_out[16], @ciphertext)

BTW, you're making your life hard by translating the ASCII to hex by hand. Let the Spin compiler do that for you. Just enter your byte data as strings enclosed in quotes.

-Phil

Don M

Thanks Phil! That works. Happy Easter!

Duane Degn

You also add another name to the second half of the array.

data_out0      byte $32, $2e, $30, $30, $2c, $52, $30, $30, $43, $30, $30, $2c, $4d, $41, $43, $3a       
data_out1      byte $30, $30, $30, $37, $38, $30, $37, $46, $41, $38, $44, $33, $00, $00, $00, $00

data_out0[16] references the same element as data_out1[0].

Don M

Duane Degn wrote: »

You also add another name to the second half of the array.

data_out0      byte $32, $2e, $30, $30, $2c, $52, $30, $30, $43, $30, $30, $2c, $4d, $41, $43, $3a       
data_out1      byte $30, $30, $30, $37, $38, $30, $37, $46, $41, $38, $44, $33, $00, $00, $00, $00

data_out0[16] references the same element as data_out1[0].

Thanks Duane. That I already knew I could do but wanted just one data name to deal with.