If you are trying to convert the RS232 signal to another signal such as the RS422 then your will need a RS232 – RS422 converter to achieve this. The XS202 from US Converters LLC is a bi-directional RS232 to RS422 converter which is port powered how you can add additional power if needed such as an external 5VDC power source which needs a 6 pin DB9 Terminal Block Header.
RS232 – RS422 Converter
The converter allows for 300 – 115200 bps transmission speeds. It also allows for support of 4-wire balanced full duplex communication completely bi-directional. The converter does not require a driver or any other software as it uses the MAX491 processor chip. No external power source is required and the converter is non-isolated and is completely plug and play.