This instruction Skips the next half-words if the register is Not Zero.
The 4-bit SRC2 field contains the Skip Length, a signed integer (between -8 and 7) that indicates how many half-words must be skipped (from the instruction's opcode address).
The Imm16 field is used to XOR the register with a sign-extended 16-bit immediate value, so the register can also be tested for inequality with a 16-bit value.
This is one of the instructions of the SKIP group, see also : SKIP, SZ, SO/SNE/SNO/SE, SS/SNS.