8051 and Tini Java Presentation

Notes.   By Andrew Oswald for Robotics I, Spring 2003


   The 8051 was developed by Intel in the late 80's, as a replacement for the 8048 (or IBM PC Keyboard controller fame).   The basic chip was available in EPROM (8751), masked ROM, or no ROM versions.   There are now dozens of variants available from a variety of companies.   The integrated i/o subsystems have been expanded on various chips.   Newer versions can contain USB interfaces, Ethernet, Data Acquisition Systems, Flash, etc.  

But the original chip came with the following features that tend to be common to most of the later chips:

Dallas Semiconductor -- Loves batteries.

Tini -- the 8051 with Java

Tini is a 72 pin SIMM sized pc board containing an 8051 variant that will run Java.   This allows the application code to be written with a common high-level language.

The Hardware Contains:

When the board boots, you can then log into it via the serial port or Ethernet, and it will drop you into "slush" it's shell.   The Java virtual machine is 40k and supports threads, all primitives, strings, native methods, and has a garbage collector built in.   The only missing features are dynamic class loading and object finalization.

The schedule updates as follows:
There is also a full TCP/IP stack, web server, PPP, FTP and telnet support.

One-wire -- a Single Wire Input/Output System

One-wire is a single wire data/power multidrop bus and a ground connection that allows a variety or memory, input and  output devices to be hooked to and controlled by a single port pin.   Originally designed for process control monitoring, the bus has been  a popular technical approach to security systems, since the cable runs can be long, and many of the devices have been packaged in a rugged watch battery can that can act like a key.

All one-wire devices have a unique serial number that is used for addressing on the bus.   Initially they also contained RAM, or EPROM that configuration information can be programmed into.   What becomes interesting is when Dallas developed devices that have inputs and outputs.   This allows for the development of interesting networks of sensors and actuators.    

One example of what can be done with all of this technology is my robot that can be controlled from a web page on the Internet.

Internet controlled robotic base.