Mod-RSsim (often stylized as ) is a popular Modbus serial and TCP/IP slave simulator. It allows users to:
: Introduce CRC errors, timeouts, and framing issues to test system robustness. The "Registration Key" Mystery mod-rssim registration key
Historically, Mod-RSsim was released as a under the GNU Affero General Public License . In its most widely used open-source form, it does not require a registration key for full functionality. Mod-RSsim (often stylized as ) is a popular