BS2 IC

t88 · September 29, 2010, 11:42am

Hi.

I need some advice on how to draw up the schematic for a series B female usb, i need to connect to a BS2 IC, and my pc does not have an RS 232 port. Can i just make the connection on the PCB or do i need any components between the ubs and the ic’s programming pins.

Regards

robotfreak · September 29, 2010, 3:17pm

You will need an USB-UART

You will need an USB-UART Chip, like the FTDI FT232 or an ready to use USB UART Adapter, like the FTDI Basic from Sparkfun. The BS2 uses inverted UART signals, like the PICAXE. You can change this in the FTDI Chip with the FT_Prog utility. I’m not shure about the output voltage of the BS2. Maybe a level shifter is needed, a MAX232 for example. The MAX232 also inverts the signals.

t88 · October 19, 2010, 6:26pm

Thanks, I got an RS 232 to

Thanks, I got an RS 232 to USB adapter cable with the USB-UART chip integrated into the cable, the output on the BS2 is 5 volt. Will I be able to run the coding software from windows 7 or do I need XP? Can’t I just run it as admin under compatibility mode on windows 7? I see in some schematics the BS2 IC has 2 X 0.1uF caps on the ATN and VSS pins that connect to the pc? Is this a must or what is the function of these caps?

lexlee · October 24, 2010, 9:25am

Sth similar

Hi, this is a schematic for the Parallax Penguin, which runs on BS2px.

pauljd · October 24, 2010, 8:20pm

Hi T,if you have the

Hi T,

if you have the parallax rs232 to usb converter, I would just use that. I agree with robotfreak, you would need the FTDI chip to go usb to usb, but thats just going to complicate your project. I just went through all of this with my compass bot, where I made my own circut board using the BS2 module, and because I couldnt find locally a 9pin female right-angle connector, I used a 4 pin header hookup system connecting to a 9 pin female, which receives the connection from the parallax rs232-usb converter. although it’s hand-drawn, I show a schematic of how I hooked it up.

I dont know enough about electronics to say why you say need those 2 caps on the serial line, but I assumed I needed them, so I used them, and they work. they are the same 2 little caps included in several of their educational kits. (small yellow-ish)

I am using windows 7 with the pbasic editor 2.5, with a usb cable and their usb-rs232 converter. I did not have to make any special setups to use the pbasic editor 2.5

I’m not using the pin 24 - VIN, and instead, I’m using a 5v regulator, and applying 5v to pin 21 - VDD, for 2 reasons. 1 - why make the BS2 perform voltage regulation, shortening its life. and 2 - if you rely on pin 21 for VDD 5v output, your limited to 50ma.

t88 · October 25, 2010, 5:07am

Thanks PaulHow good are you

Thanks Paul

How good are you with software? I need to get a 3 axis milling machine working with the BS2 connected to my PC. I basically want to “print” the drawing from Autodesk inventor to the BS2 and let it do its work, but I am an amateur with both Pbasic and c++, I am currently getting to grip with Pbasic.

Is what I am trying to do even possible? Can you give me some tips on what to look for?

pauljd · October 25, 2010, 7:45am

I’ve been programming

I’ve been programming computers since 1977, professionally since 1981, self-employed since 1984. every job I do is custom. never the same job twice.

In that time, I’ve learned anything is possible. its just a matter of how much time and effort your willing to put into it. and of course a healthy budget is sometimes required.

I dont know anything about autodesk inventor. what kind of output does it generate? lots of cnc code?

whats the story behind the milling machine? is it homemade? does the manufacturer provide guidance on how to interface to it, or what kind of code it expects from the PC? can the manufacturer provide samples of how to use the machine?

if I was to get involved with a project like that, I would need a sample machine to play with, and assuming the machine is in good working condition, at least 3 - 6 months of spare time.

I guess your starting point would be to establish basic communication between your pc and cnc machine. your BS2 program would probably be the type that reads a file containing a string of cnc codes. the bs2 would read those codes and know how to translate that into specific actions, such as: start rotation, plunge tool 5mm, move tool along X-axis 10cm, raise tool, etc… 3 huge factors would be calibration, scaling, and offsets.

your BS2 program would have to be aware of all the abilities physically built into the machine.

can you post some pictures, or schematics of the cnc machine, or manufacturer and model #, etc. then I would try to contact manufacturer for guidance, samples, etc.