Can I specify more than one port to REDIRECT_STRING from/to?
While there can be up to eight REDIRECT_STRING operations at a time, they cannot share devices. Programmers cannot redirect from 1 to 2 and from 1 to 3 at the same time. Consider REDIRECT_STRING to be a point to point connection.
When programming the string as "REDIRECT_STRING(1,RS1,RS2)", could you confirm the delay time length generated between the command received by RS1 and output thru RS2?
In Axcess, the delay time is affected by program size and time to execute mainline. In NetLinx, it is affected by the same items as Axcess, along with other things like Web Interface traffic, FTP interface traffic, IP communications and message queue traffic. There is no maximum time delay length that can be set for a limit, although in "normal" operation, there should be no perceivable delay.
In general, using the REDIRECT_STRING will function faster for transferring data between two devices than programmers could do by explicitly writing the transfer in Axcess/NetLinx code. That is the benefit of REDIRECT_STRING.
When using the "REDIRECT_STRING", could you advise how to enable error checking of transmission error within AXCESS or NetLinx?
There is no method to handle transmission error. What is received in one device (whether correct or erroneous) will be transmitted out the other.
When using the "REDIRECT_STRING", in case of receiving quite a large amount of data externally, is it possible to lose data?
Yes, it is possible to overflow, depending on what devices are used and the baud rates. Some devices use much larger size internal buffers than others (i.e.; a NetLinx NXC-232 vs. an Axcess AXC-232) and the internal buffers could be overflowed. This could also be affected by baud rate differences by devices (i.e. one device is using 38400 vs. the other at 1200). Again in "normal" conditions, there will be little potential for errors.
When using the "REDIRECT_STRING", are communications run thru Master or directly enabled between ports?
In Axcess and NetLinx, REDIRECT_STRING is handled by the master.