Project193

Main Controller: Bottom (left) and Top (right) Boards

Project193 involves the development of a real time robotics controller with an emphasis on educational use.  The hardware is being developed as part of my Masters research at The Ohio State University.  This section will feature primarily the hardware design of the main controller, which I have been been completing.  The main controller consists of:

• Intel 80C196NT CPU at 16Mhz (capable of up to 20mhz)

• 512k AMD FLASH memory

• 64k Cypress SRAM

• Cypress Master/Slave USB interface

• Phillips high-speed I²C bus master

• A graphical LCD display (not implemented yet)

• LM80 power management chip

The main controller is divided into two boards which mesh via a standard 40-pin interface.  The boards are commonly referred to as top and bottom.  The bottom board contains the CPU, memory, and discrete logic for address decoding and peripheral selection.  The top board contains the communications chips, power supply, and human interface devices.  The idea behind this is that the core will always remain the same no matter what the application, but specialized top boards can be remanufactured to add or subtract various peripherals as needed.

The Board "Sandwich"

• Top Board Design

• Bottom Board (Roxy) Design

• I²C Test Module Design

• FLASH Programmer Design

The idea behind the controller involves making a number of peripherals which don't appear on the top board modular via the on-board I²C bus.  For example, modules may consist of:

• High current motor controllers

• Servo controllers

• Extended I/O interfaces (standard digital lines or additional protocols)

• Data loggers

• Analog inputs

• Any other idea involving another device with an I²C interface

The power circuit involves both a 5V and 3.3V regulator.  All devices on the bottom board require a 5V supply while the newer communications chips (USB and I2C) on the top board require 3.3V power.  All chips are 5V tolerant so no problems occur on the data bus.

The FLASH memory is programmed via a specialized top board attachment known as the programmer.  This top board does not remain on the unit during normal operation as programming involves removing of the main CPU.  A PIC microcontroller on this specialized top board aids in the transfer of the kernel to the FLASH memory via a PC serial port.  Once the download is complete and verified the programmer board is removed and the main CPU is reinserted.  Technically the main CPU shouldn't need to be removed as jumpers are provided to put it into a non-operational state while external programming occurs.  This is currently untested though as it is not difficult to just remove the CPU instead to avoid bus conflicts.

• Programmer Board Design

Development Space

While OSU has given me a small area to work on design and development, I have found that my home "lab" is actually better equipped in terms of equipment (sad but true), internet connection, and convenience. 

• My Home EE Lab

For more information contact beams.2(at)osu.edu.