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What programs can act as a terminal and access serial ports?

This is not for terminal access on an IP connection, this is so I can access a hardware device plugged into a USB/serial converter running at 9600/8/N/1.

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You mean like a modem port 20 years ago? –  patrix Dec 2 '11 at 18:29
@patrix, yes. I can load vmware, run windows, and use putty, but that seems like a lot of trouble to perform such a simple task. –  Mark Harrison Dec 2 '11 at 18:33
Lol. 9600/8/N/1. like a mantra to me. you can use zterm which still works at least up to 10.6. It old software. But was built to configure , communicate with Modems and transmit files modem to modem. dalverson.com/zterm –  markhunte Jan 3 '13 at 0:11
The latest zterm works with 10.9. –  Dan Pritts Mar 23 '14 at 18:35

7 Answers 7

You can use the terminal command screen to do this!!!

As seen on ServerFault:

I love using [screen] for connecting to serial consoles, i.e.

screen /dev/ttyS0 19200

Or, if you prefer Mac OS X hints...

I often have to do router configuration via a console port, so I use a Keyspan Serial Adapter to get access. Two problems then present themselves: ZTerm is a horrible Mac OS X app. It hasn't been updated in five years or so, and isn't a Universal Binary. The developer doesn't seem in any hurry to rectify the situation. It is not worth the shareware fee in its current form. Minicom requires installation of Fink or MacPorts and is overly complex. Solution: Use screen, Terminal, and a little AppleScripting.

First, launch Script Editor and type/paste in the following code:

tell application "Terminal"
  do script with command "screen /dev/tty.KeySerial1"
  set number of rows of window 1 to 100
  set number of columns of window 1 to 80
  set background color of window 1 to "black"
  set normal text color of window 1 to "green"
  set custom title of window 1 to "SerialOut"
end tell

Compile and save as an app from within Script Editor, and you have a double-clickable application to launch a serial Terminal session. You may want to customize this slightly -- you can change the screen colors or number of columns or rows. You may also need to customize the screen command with a different device name if you are using something other than the Keyspan Serial Adapter (do an ls tty* of the /dev/ directory to get the right name).

screen uses Control-A to take commands directed to it. So type Control-A followed by Control-\ to exit your screen session. If you fail to do this and exit a Terminal session, you'll leave the screen session alive and the serial resource unavailable until you kill the screen session manually. man screen will show you further commands to send to a screen session.

If anyone can reply with a link to a tutorial on how to wrap an interactive Unix App in Cocoa, that would be the next step -- it would be nice to do this without involving Terminal. If you prefer to use Minicom, you could still use the AppleScript to wrap it into a nice launchable app -- use this older hint to find the right command line commands.

Many USB-Serial adapters use the chip from FTDI. Install the "Virtual COM Port" driver and look for the proper TTY name in /dev. For example, on a PowerBook G4 it came up as /dev/tty.usbserial-FTALKY8I.

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For USB-Serial adapters with PL2303 chip, see sourceforge.net/projects/osx-pl2303 –  Dan Pritts Mar 23 '14 at 18:37
Clearly the best answer: Terminal + screen + osx-pl2303 (in production use since… many years ☺). –  daniel Azuelos Aug 4 '14 at 16:49
It's worth looking at Chris K's answer below; apparently OS X comes with FTDI drivers since 10.9 (after this answer was written), so the installation isn't necessary. –  krs013 Dec 8 '14 at 19:16

There's a new Mac app called Serial, available in the app store. Full disclosure- I wrote it. The main advantage over other apps is it can work with most USB to serial devices without having to install any drivers, as it has its own drivers built-in. It also does full terminal emulation so you can use it to work with Linux or other devices that require it. You can try it for free, too.

Also, Apple began including their own driver for FTDI-based devices in Mavericks (10.9). So, if you're on 10.9 or later and your device has an FTDI chip inside, you can use the built-in screen command in the terminal to access your device without worrying about drivers.

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I just tried Serial today. So far, I'm quite impressed. I'll purchase it just for sparing me from having to worry about USB to serial drivers. I won't miss ssh'ing into my Linux box to run minicom. –  Daryl Spitzer Feb 13 at 0:16

The best program I know of for this is minicom, available from Homebrew, fink, and macports.

Minicom is a serial communication program. It is a Unix clone of the well-known MS-DOS Telix program. It has ANSI color, a dialing directory, dial-a-list, and a scripting language.

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The meta key is Esc. So Esc-Q to quit, Esc-O for options, etc. I found minicom (and Serial.app) to be best at handling disconnects/reconnects which are basically implicit when running LinkitOne (all Arduino?) development. Most other apps crash or lose the connection and cannot reconnect until relaunch. –  owenfi Mar 18 at 5:10

If you prefer not to work in Terminal, you might mant to try CoolTerm (free). Scroll down a bit for description and download. Don’t let the fact it‘s written in RealBasic turn you away... I have used it to connect to plotters, Arduino boards and receipt printers via a Keyspan USB<->Serial Adaptor.

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You should have a look at ZOC, what I think to be the best terminal emulation program available for the Mac. I use it everyday for my job. It has the ability to do direct communication with a serial port. Of course it does way more than just serial communication.

ZOC is a professional SSH/telnet client and terminal emulator. With its impressive list of emulations it lets you easily connect to hosts and mainframes, using communication methods like secure shell, telnet, serial cable or modem/isdn.

Its sleek user interface has many ways of making your life easier. In its own way, this is the swiss army knife of thin clients: versatile, robust, proven.

Key features:
- Tabbed sessions with thumbnails
- Customizable to meet your preferences and needs
- Scripting and automation features
- Compatible with Windows 7 and OS X Lion
- Administrator friendly (deployment, configuration)
- Now $79.99 with attractive bulk discounts

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80$ for a terminal emulator seems a bit steep if he just needs that feature! –  Agos Dec 2 '11 at 23:42
Price was not mentioned as a criteria in the question. Please don't diminish an answer just because you don't agree with the price. –  Carter Dec 3 '11 at 13:11
I second Agos' comment. He's not "diminishing" your answer, just saying that he thinks that ZOC is not a good solution considering everything (cost, features, etc) –  cyphunk Jul 11 '12 at 7:57
Also, combined with the other answers above, it seems (from the quoted description) like the only difference between ZOC and Terminal is tab thumbnails (and the price). –  Matt Aug 2 '12 at 16:15

C-Kermit is alive and well in Brew, and can be installed with:

% brew install c-kermit

You, of course, have to have Brew installed.

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And then there still is the old ZTerm which is just as old as it's looks suggest yet it gets the job done just fine and it is available for free. Works fine with Prolific (PL 2303) and FTDI based USB serial adapters.

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Wow, ZTerm lives! Brings backs many memories and old Macs. –  lhf Jun 7 '14 at 15:08

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