OS for use over serial port

[da na]

This is quite a strange question, but I am searching for an operating system which can be used exclusively through a serial port.

 

I recently acquired a Cisco ASA 5505, a small network appliance with everything required to qualify as a computer. It has an x86 CPU, 512MB of RAM, boots from an ATA interface drive, and has a BIOS.

However, the only output of the system is serial; it lacks any sort of video out. This complicates my wish to hack it.

Is there any operating system which will recognize (and be okay with) the complete lack of any video hardware and direct all interfacing to the serial port? I essentially want to use the ASA 5505 as a mainframe. 
I can access the device and send it commands via serial console via its built-in firmware, but I would like to run DOS programs. 
Is this even possible, or should I start looking at the pinout of the southbridge chipset to see if I can hack in a composite video port?

Thanks! 

[Needfuldoer]

The bigger question is, will Cisco's firmware and bootloader let you install anything but Cisco iOS? I doubt it will.

 

I'd go with something more standard like a mini PC or a Raspberry Pi if you want something that's only accessible by command line over serial.

[Sanedish]

I'm pretty sure there's gonna be an debian version made to run over serial, maybe an console only one?

If you need help choosing an os, i can trynna help you, but i'm just assuming from experience on other devices. i have never in my life tried to run cmdl only linux on a networking switch before [!!!]

[da na]

1 minute ago, Needfuldoer said:

The bigger question is, will Cisco's firmware and bootloader let you install anything but Cisco iOS?

Probably not. That's why I want to try a little.

[LloydLynx]

That's the one with ethernet ports right? Install an MBR 32bit OS on another machine and swap the drive into the Cisco, access the OS remotely through the network.

[da na]

29 minutes ago, LloydLynx said:

That's the one with ethernet ports right? Install an MBR 32bit OS on another machine and swap the drive into the Cisco, access the OS remotely through the network.

Unfortunately I have tried that with FreeDOS and... well, I assume it's booting, I hear the hard drive ticking for a bit after the bootloader runs from the onboard flash, but I get no output over a serial console session.

[LloydLynx]

8 hours ago, da na said:

Unfortunately I have tried that with FreeDOS and... well, I assume it's booting, I hear the hard drive ticking for a bit after the bootloader runs from the onboard flash, but I get no output over a serial console session.

Machine 1, this will be our server: Install this Debian version to a hard drive and choose the XFCE desktop environment when it asks. After booting into the new Debian installation, install the openssh-server package. Edit the file /etc/ssh/sshd_config and change "#X11Forwarding no" to "X11Forwarding yes". Run "sudo service ssh restart".

 

Machinie 2, this will be our client: From a machine on the network also running Linux, install openssh-server and do the same edit to /etc/ssh/sshd_config and restart the ssh service, exactly like the first machine. Now from a terminal, remotely log into the first machine with "ssh -X <username>@<ipaddress>" which will give you a remote bash console. Now you can launch graphical programs and have them show up on the client machine. Last step obviously is to move the hard drive into the Cisco and try remotely logging into it.