For US demo merchant accounts

AVS
In order to simulate an AVS response in the demo/test environment, you can set the first character of the address value to the desired AVS response code. 
For example, setting the address value to "N123 Main St" for a transaction would simulate the AVS response code "N".  If the transaction is processed under a terminal that has the "No match" AVS filter checked, the transaction will be declined due to failed AVS verification.

CVV2
In order to simulate a CVV2 response in the demo/test environment, you can set the first character of the verification value as follows:

First Character Example Verification Value CVV2 Response CVV2 Filter Name in RPM Terminal Administration
1 123 M Card is authentic
2 234 N CVV2 does not match
3 345 P Card expiration not provided or card does not have valid CVD code
4 456 S Merchant indicated that CVV2 is not present on card
5 567 U Card issuer is not certified and/or has not provided visa encryption keys