Home > Articles

  • Print
  • + Share This
This chapter is from the book

The OpenBoot Interface

The OpenBoot firmware provides a command-line interface for the user at the system console. On older Sun systems such as SPARCstation 10 and SPARCstation 20, this command-line interface had two modes: the Restricted Monitor and the Forth Monitor.

The Restricted Monitor

The Restricted Monitor provides simple sets of commands to initiate booting of the system, resume system execution, and enter the Forth Monitor. The Restricted Monitor is also used to implement system security.

The Restricted Monitor prompt is > (the greater than symbol). When you enter the Restricted Monitor, the following code displays, showing the commands you can enter:

Type b (boot), c (continue), or n (new command mode) >

The Restricted Monitor commands are listed in Table 3.1.

Table 3.1 - Restricted Monitor Commands




Boots the operating system


Resumes the execution of a halted program


Enters the Forth Monitor

The Forth Monitor

The Forth Monitor, the default mode in OpenBoot, is an interactive command interpreter that gives you access to an extensive set of functions for hardware and software diagnosis. You'll also see the Forth Monitor referred to as new command mode. These functions are available to anyone who has access to the system console.


Switching from the > Prompt to the ok Prompt When the system is halted, the PROM monitor prompt displays. The type of prompt depends on your system type. Older Sun systems use > as the PROM prompt. Current Sun systems use ok as the PROM prompt but support the > prompt. To switch from the > prompt to the ok prompt on newer Sun systems, you type n at the > prompt.

The Forth Monitor prompt is ok. When you enter the Forth Monitor mode, the following line displays:

Type help for more information 

On older Sun SPARCstations, if you want to leave the Forth Monitor mode and get into the Restricted Monitor mode, you type the following:

ok old-mode
  • + Share This
  • 🔖 Save To Your Account