User's Manual

Page 77 of 83

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needs. LogicLoader can also be augmented with functional test software to completely verify a device

before it leaves the manufacturing line. Here is an example scenario: LogicLoader could launch a

device’s final functional test at the end of a manufacturing line, and then load the device’s final

software image before packaging. Contact Logic for more information on using LogicLoader to

streamline manufacturing.

The LogicLoader Shell (loshTM)

Losh Overview

Losh is a command interpreter similar to those found in Unix environments. Losh implements a

rudimentary network and file system command set, enhanced with custom diagnostic and memory

manipulation commands for debugging hardware.

Developers familiar with a Unix-like command line interface should find the losh implementation familiar

and easy to work with. Many of losh’s commands are patterned after their Unix counterparts and share

the same syntax.

Losh Basics

Losh uses a standard output stream (stdout). By default, stdout refers to a SOM’s debug serial port. The

output of any command that displays information to stdout (i.e. the ‘cat’ command) can be viewed

using the terminal emulation program connected to the SOM’s debug serial port. Likewise, the

standard input stream (stdin) by default also refers to the SOM’s debug serial port.

The LogicLoader Shell includes a virtual file system that uses standard Unix path names. The highest-level

(or root) directory is designated by the identifier ‘/’. A special sub-directory of the root with the name

‘dev’ is used to enumerate and interact with system’s various peripherals and their associated device

drivers.

Using Losh

The losh shell includes a basic command line editing feature and a command history feature. This provides

users with a quick way to repeat commands. Using the up and down arrow keys, the user can scroll

through the list of previously executed commands. When a desired command is displayed, press the

return key to repeat the command. The right and left arrow keys allow a user to position the cursor as

desired on the current line so that text can be modified, deleted, or inserted at the appropriate location

without having to “backspace” the entire line to access the portion of the command or command set

being entered.

Losh includes a user help feature through the ‘help’ command. Typing ‘help’ followed by any command

name at the losh prompt will display the command’s syntax, usage, and an example. This may be

especially helpful to users who are just becoming familiar with the LogicLoader shell.

Commands may be run in the background by adding a ‘&’ suffix.

Program Loading

Using LogicLoader to download any application, operating system, or update to a device requires an

understanding of the interaction between the ‘load’, ‘burn’, ‘jump’, and ‘exec’ commands. The

purpose of this section is to explain the interaction of these commands.