SerialTCP allows you to instantiate and send a TCP or SSH connection to any available serial port on your Macintosh. It’s free, and compatible with Mac OS X (Intel) 10.6 and above.
Use SerialTCP to link a legacy device with a serial port to a server on the internet. It’s perfect for retro computing hardware, so you can connect, say, your Commodore C64 to take advantage of services like Q-Link Reloaded, CommodoreServer.com, and internet enabled BBSes. It emulates a limited Hayes Compatible command set, so you can “dial” into servers directly from the device on the serial end.
Download – Version 2.0
Note: If the version of Mac OS X you are running supports App Nap, turn this feature off for SerialTCP. Right click on the application icon, select Get Info, and check “Prevent App Nap” under General. Failure to do this will result in serial data lag when SerialTCP is not the frontmost application.
In order to connect your Mac to older hardware, you may need a USB to RS-232 interface. May we suggest the Plugable USB to RS-232 Serial Adapter. It utilizes the highly compatible Prolific PL2303HX Rev D Chipset and comes with driver software suitable for all versions of OS X.