RE: Nemesis4Lego controller

Gabriel,

If you decide to make up some of these I would be interested in a few. In the 
mean time could you share more details about what you did? Can you provide 
schematics? It is difficult from the Kronos web site to get a feel for how 
large of a program the Nemesis can support. Can you give us a feel for how the 
Menesis compares to the RCX in terms of the complexity of the tasks that each 
can perform given their program sizes?

Chris

-----Original Message-----
From: news-gateway@xxxxxxxxxx [mailto:news-gateway@xxxxxxxxxx] On Behalf Of 
Gabriel Petrut
Sent: Tuesday, May 31, 2005 7:42 PM
To: lego-robotics@xxxxxxxxxx
Subject: Nemesis4Lego controller


Danny & all,

This was a prototype that I have built with regular parts. If there will be 
demand, I will make and order PCBs. The total cost of the parts is around $30. 
Add $10 for labor (and that is verry modest) and you'll get the price. The size 
can be even smaller than what I ended up with! I mean the height can be 1 plate 
(for contacts) at the bottom, 1 brick, 2 plates on top.

KronosRobotics are the manufacturers of the microcontrollers. Michael Simpson 
has taken a 16C84 or something like that and created a firmware and uploaded it 
into these chips. And he created the free software (Basic) so anyone can 
program them pretty easily. They work like a BasicStamp controller. And the 
software has a Simulator and a Debug window, where you can see the sensor 
values, etc. so you don't realy need a LCD.

They have 2 controller classes: Dios and Athena. Dios is more powerfull and 
bigger. Athena is cheap, low speed and memory. In Athena class there are 3
controllers: Athena ($6.95), Perseus ($8.95) and Nemesis ($12.95). Athena and 
Perseus are great to make the slaves and Nemesis the Master. These controllers 
do not support multitasking.

However, IF someone (i.e. Michael Simpson) agrees to modify the firmware, They 
can be perfect for small Lego controllers. What needs to be modified? The IR 
protocol for instance, to be able to work with Lego Remote and talk to RCXs. 
Perhaps he will do that if there is a real demand.

Mean while, I will try to make it work, allthough it is verry hard for me. I am 
not an engineer and I do not understand the terms and how IR and serial 
protocols work. All I did was put together some examples and application notes 
from their website. And after I have read the Boe-Bot manual I understood how 
to use the Panasonic IR sensors to do proximity detection and even distance 
measurements (left and right).

The controller that I have built (put together) can work with up to 7 Lego 
active sensors. I have chosen to make it work with only 2, so I can use another 
2 input/outputs for 3 pin sensors or to command 2 servos. And of course, 2 for 
the IR sensors. Actualy, I have seen that it can be done with only one sensor 
with 2 separate IR Leds. Fire left - measure, fire right - measure. Also, the 
motor driver has an Enable pin that can be used to ramp up/down the speed verry 
smooth. The motors are running at 9v like on a RCX.

There are more ways to do a master-slave comunication with these controllers. I 
thought the easiest way to do it will be using the serial bus that is used to 
program them. This bus has 5 pins: -,+(5v),Rx,Tx,Atn. I am considering adding 
another pin for +9v, so they can get power from the Master - for the motors. 
Or, have the slaves have their own Lego power connector...


Possible Slaves:

2 sensors slave, using a Athena micro.
4 sensors slave, using a Athena micro.
2 sensors, 2 motors slave, using eighter Athena or Perseus (faster) micro. LCD 
slave, using a Athena micro. Speak slave, using a AthenaHS and a SpeakJet.

All the slaves can have up to four 3 pin ports to connect to servos or 3 pin 
sensors.

All in all, this is a fun project for me, and if there is a real demand, I will 
consider building more units. I will make some Slaves for myself and keep you 
all posted with the results.


Gabriel