- port->timeouts.ReadIntervalTimeout = 0;
- port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ if (port->timeouts.ReadIntervalTimeout != 0 ||
+ port->timeouts.ReadTotalTimeoutConstant != timeout_ms) {
+ port->timeouts.ReadIntervalTimeout = 0;
+ port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }