RS232 and RS485 are completely different standards. They both use serial data communication - but that's all they have in common.
They use different voltage levels, and many RS232 communication protocolls use hardware handshaking, i.e. control lines. In most cases RS485 does not use control lines, and the data transmission is done via a pair of lines which serves for transmitting and receiving data (bi-directional). (There are some RS485 interfaces which use control lines but these also have voltage levels different from RS232).
There are level converters available, but since RS232 often uses hardware handshaking they may not work in your application.
