My RouterBoard 433 will boot beep once, then later beep twice in a higher pitch, I have no ethernet access.

I used HyperTerminal and a correct Null-Modem Serial cable, I connect with 9600 bits per second; 8 data bits; no parity, 1 stop bit and hardware flow control.

My problem is, I receive nothing but random text characters when I boot up the RouterBoard.

Does the RouterBoard require a certain Emulation setting?

How would I go about fixing this problem, I need to reinstall the RouterOS but can not access the BIOS on the RouterBoard.

Some of your connection settings are wrong.
Take a look at the Quick Setup guide here. http://www.routerboard.com/pdf/rb433mA.pdf

-Louis

default baud rate for 400 series is 115200 bps not 9600

Many folks who are trying to connect to a serial terminal / console session may be trying to re-establish administrative control after making a mistake in their firewall rules. This happened to me a few days ago, and I struggled and struggled to get the serial cable/session going. For everyone in that boat, there is an easier answer:

1) Download and unzip "Neighbour viewer for Windows" free from the Mikrotik web site.
2) Install it on a PC local to the router (not behind another router).
3) Get it to 'discover' your router, then press the button to initiate a terminal session (using its own built-in terminal that connects by MAC address, not by IP)
4) Log-in to the terminal session like you would any other SSH session. Fix your firewall so that you can again connect by your method of choice.

No serial cable required.

easier would be to use winbox to detect neigbours and click on mac address to connect to router, that will use mac-winbox.

@janisk A cold one to you pal! You just saved my router, I was prepared to take this thing apart and hardreset it via terminal short.