Hi, Its been a long time since I last used a PICAXE chip, and some of the products have changed a little. Hence, this post.
To add a little background.....
I dont know how many people have heard of the Bloodhound SSC. Its a new project to create a car capable of going over 1000MPH. Now these people are keen to get year 9 students involved in engineering, and my old School has taken the challenge. As part of their CDT lessons they are given a block of foam that they can shape aerodynamically.
This is the fun bit.....
in the back is placed a rocket motor.............
Their cars will be guided by a peice of wire so as they dont go off course.
My challenge is to create a timer system using light gates to time the rockets through a 10m distance (at a resolution of 10 milliseconds or greater). This time can then be used to create a speed in m/s, and thus MPH and display it on a AXE033.
The light gates will simply be an LDR and a laser diode spaced around 30cm apart.
My main question is:
a few years ago I would have bought just a 28X and be done with it. but you cant buy them anymore.. and the new 28x1 and 28x2 dont come with external resonators... I know I can add external resonators to these chips, but is it worth it?
What are the benefits of the 28X1 over the 28X2?
and if an external resonator is useful, what size would be best suited 4Mhz, 8Mhz or 16Mhz?
I know this post is long, sorry, you have finally made it to the end...... congratulations!!!
Thank You,
Owen.
To add a little background.....
I dont know how many people have heard of the Bloodhound SSC. Its a new project to create a car capable of going over 1000MPH. Now these people are keen to get year 9 students involved in engineering, and my old School has taken the challenge. As part of their CDT lessons they are given a block of foam that they can shape aerodynamically.
This is the fun bit.....
in the back is placed a rocket motor.............
Their cars will be guided by a peice of wire so as they dont go off course.
My challenge is to create a timer system using light gates to time the rockets through a 10m distance (at a resolution of 10 milliseconds or greater). This time can then be used to create a speed in m/s, and thus MPH and display it on a AXE033.
The light gates will simply be an LDR and a laser diode spaced around 30cm apart.
My main question is:
a few years ago I would have bought just a 28X and be done with it. but you cant buy them anymore.. and the new 28x1 and 28x2 dont come with external resonators... I know I can add external resonators to these chips, but is it worth it?
What are the benefits of the 28X1 over the 28X2?
and if an external resonator is useful, what size would be best suited 4Mhz, 8Mhz or 16Mhz?
I know this post is long, sorry, you have finally made it to the end...... congratulations!!!
Thank You,
Owen.