Ok, I am now trying to understand the connection options. By looking at the "Channel Configuration Setting Tabs". General Tab looks to be a summary of Channel 0 and 1 settings. "Channel 1 System" Tab looks to be the configuration for the top 2 plugs DH+ (the Blue Tube connector and a round connector) on the SLC 5/04 CPU card. If that's where or how you connect. "Channel 0 System Tab" looks to be the configuration for the bottom RS 232 plug on the SLC 5/04 CPU card. If that's where or how you connect.
That is all correct.
I'm not clear on the difference between DH-485, DF1 or ASCII.
The CH0 port (bottom D9F serial connector) is RS-232 electrically, but supports several different protocols. DH-485, DF1, and ASCII are different protocols. Since your PLC is set up for DF1 Slave, Ken Roach gave the best answer for how to set up a driver in RSLinx to connect to that port.
Be aware that you must get the baud rate, data bits, parity and error checking mode matched up in order to succeed. It has been my experience that if you miss one of those items, the driver won't let you go back and change it. Even if you stop the driver first, I seem to recall not being able to change those details, so I would have to delete the driver and then recreate it. It is usually on a telemetry system talking to a Micrologix 1000 over a radio modem where I see DF1 Half Duplex, and that little brick won't let you switch modes and I think uses BCC error checking.
Also, you may have to stop other drivers (if you have any) that are set up in RSLinx and assigned to the same Windows COM number.
I have successfully used the DF1 Polling master driver in Windows 7 and Windows 10 with a
good quality USB to serial converter.
I'm am not understanding the difference between "Channel0 System" and "Channel 0 User" Also, I need to understand how to move forward. Since the PLC is configured DH+ according to the Channel 1 Configuration settings, and the Channel 0 Configuration set to Half Duplex Slave which is not the most user friendly connection method, I need to be able to connect DH+ via one of the top 2 ports. Then transfer/upload the program in the PLC to a laptop, change the Channel 0 Configuration to ________, save the program than transfer/download the program to the PLC. Now I should be able to connect via Channel 0 with my 1747-CP3 RS232 to Com port cable.
In a SLC, it is possible to have a System and User mode that is changed via PLC code. Typically, this is done when you have an ASCII device and still need to be able to use the PLC with RSLogix on Channel 0. You could program a discrete input or any other imaginable condition to select User Mode or System Mode in PLC code. This feature is rarely used.
I would go forward by attempting to use Channel 0 and the Polling Master Driver. Be patient with it. Even after it is set up properly, it is slow. It can take a minute just to show that the SLC exists under that driver in RSLinx even if everything is set right. If you exhaust that avenue, then appropriate for yourself a U2DHP cable. Or sweet talk your local AB rep into helping out (also good advice from Ken).
Once you get online, i highly recommend changing that serial port setup to the default, DF1 Full Duplex, 19.2k baud, No parity, CRC Error checking.