Each Opera Cake has a numeric address set by optional jumpers installed on header P1. The default address (without jumpers) is 0. The
-l option can be used to list the address(es) of one or more Opera Cakes installed on a HackRF One:
The address may be set to any number from 0 to 7 by installing jumpers across the A0, A1, and/or A2 pins of header P1.
|Address||A2 Jumper||A1 Jumper||A0 Jumper|
When configuring an Opera Cake, the address may be specified with the
hackrf_operacake -o 1 -a A1 -b B2
If the address is unspecified, 0 is assumed. It is only necessary to specify the address if the address has been changed with the addition of jumpers, typically required only if multiple Opera Cakes are stacked onto a single HackRF One.