diff --git a/simulator/modbus_tcp_server_sim.c b/simulator/modbus_tcp_server_sim.c
index 76c63677..8a7a4bf5 100644
--- a/simulator/modbus_tcp_server_sim.c
+++ b/simulator/modbus_tcp_server_sim.c
@@ -216,7 +216,7 @@ int main()
             w_res->n_reg      = w_req->n_reg;
 
             for (int i = 0; i < ntohs(w_req->n_reg); i++) {
-                uint8_t x = w_u8[ntohs(w_req->n_reg) / 8] << (7 - (i % 8));
+                uint8_t x = (w_u8[ntohs(w_req->n_reg) / 8] >> (i % 8)) & 0x1;
 
                 if (x > 0) {
                     coil[ntohs(w_req->start_addr) + i] = 1;
@@ -250,4 +250,4 @@ int main()
     neu_tcp_server_close(server);
 
     return 0;
-}
\ No newline at end of file
+}