Basic Stamp Programmer

[314159]

sorry bill, i didn't agree with a couple of the points that you made.

Originally posted by billmi
In comparison to a PIC, you have to remember that a Basic Stamp is a complete computer, not just a single chip (the processor chip on a Stamp is a PIC).

the picmicro line are all complete computers (microcontrollers). they have a processor, ram, rom, i/o (sometimes eeprom, analog to digital convertes, paralell, usb 2.0 compatable, serial, i2c....)

Originally posted by billmi
To utilize a PIC you will need to design and build a circuit board with the support circuitry needed to operate the PIC as well as the interface to your paintgun. Conversely with the Stamp, all of the support hardware is on the stamp already, and you can add interface components (a MOSFET to drive a solenoid, a tie down resistor for a trigger input, for example) right on the board.

you can get pics with "all the supported hardware on them". just look for pics with an internal oscilator and internal reseting if you choose to go that route. (this will give you 2 i/o pins less than the number of pins on the package). from that point it is the same as dealing with a pbasic stamp.

Originally posted by billmi
(the PIC still needs to have a board and support hardware to be useable)

nope, the internal oscilator and the internal reset circuitry is a beautiful thing.

Originally posted by billmi
Size comparison between the stamp and a PIC isn't realistic, because you'd need to compare the PIC's size to the processor on the stamp.

it can be realistic very easy, compare the size of the pic to the size of the basic stamp

Originally posted by billmi
DIP mounted PICs (like the one to use with the programmer linked in this thread) are larger than the SMT PIC processor on the Basic Stamp.

not the programmer i posted ^_^. that just requires connection to a 5 or 6 pin header (depending on the pic) to program the pic. this can be done while the pic is in the circuit.

you could get a pic that is:
a)a dip, bigger than the pic on the stamp, but , smaller than the stamp
b)a surface mount, , even smaller than the stamp

Originally posted by billmi
Most PIC based paintgun driver boards using DIP packaged PICs, like the one in the Matrix, are in fact larger than a Basic Stamp set up for dual solenoid control of a paintgun.

they could have gone to surface mount instead of lurking in the dark side of through hole construction

Originally posted by billmi
if you're doing something that's one-off, or concentrating on getting the hardware side of something working, the speed of set-up, ease of programming (PBASIC is quite a robust language, with a lot of built in functions for signal generation, communicating with an LCD, etc.) of the Stamp give it a lot of advantages.

just buy the pbasic compilier, (it works with the pics ). http://www.picbasic.co.uk/ . you take a hit of a couple bucks at the start, but after that, you can have a $3-4 part with all the capability of the basic 2 stamp, and have it be smaller, and faster.

Originally posted by billmi
Since the Basic Stamp has programming I/O circuitry on the stamp, it doesn't need a programmer, you just need to connect it to the parallel port on a PC (You just need a DB25 connector to plug into the PC, some wire, and the connector style of your choice to plug to the stamp, I've even used aligator clips, to clip the programmer to the stamp so as to not have a plug on the board).

(simplification)you don't need a programer, you just need this device to hook it up to your computer to program it. (/simplification)

i need some time to think on this one, don't worry, i am shure that i will come up with a whitty responce

Originally posted by billmi
The PBasic compiler software that you need for programming is a free download from Parallax (www.parallax.com). The Basic Stamp manuals are free downloads as well in PDF format. I opted to buy a starter kit with a prototyping board (the boards sell for $15 seperately), the manual, a stamp, and a cable for $90. The ease of a printed manual, and knowing I had a proper cable, and an easy proto-board to work with definitely saved me time in learning

all the software you need to program a pic is free, the manuals are free too, and if you call them up, they will send you a manual for free

[314159]

bill, i took a look at the article on warpig about the basic stamp one.

there are a couple things i don't like:
-you can only make adjustments to the millisecond
-the way that you have your timing set up, you can't time things concurrently, you start something, skip x many operations, stop someting, move on.....

for a bigger solenoid, you will need a bigger mosfet (not the smaller ones that can operate a mac like valve ), for a bigger mosfet, you will probally need a greater voltage than +5 volts to get it out of the reigon where it acts like a current source, and into the reigon where it acts like a resistor to operate the solenoid, this will require some other fun tricks.

i am reminded of this quote, the key to being a good engineer is about how many tricks you can pull, it almost makes me feel like a hooker

[billmi]

Yep, EDM isn't cheap. If you have patience, a small amount of steel stock the right thickness, and a file, you can do it the old fashioned way - hand filing it to shape like a good old fashioned revolutionary war gunsmith would have done, and then harden it (I assume that can be done with a torch, if not, getting it hardened would cost a lot less than having one made).

Mind if I ask why you are putting a hole in it in the first place? I'm assuming it's to attach a pull style solenoid. Another option would to be using a push solenoid to press on the other side of the sear (push solenoids have a rod connected to the core that pokes out the back, so it pushes out when the core is drawn into the solenoid center).

See you on the field,
-Bill Mills

[314159]

lazy answer - if the holes in the emag sear would match what you are dooing, why not see if you can order an emag sear, and not a sear assembly from tom. ^_^

[hitech]

Originally posted by 314159
lazy answer - if the holes in the emag sear would match what you are dooing...

I am planning on trying this with a classic. The emag sear doesn't line up.

[314159]

i wonder if a replacement booyah, centerflag,..... sear would work?

[ShooterJM]

Originally posted by 314159
lazy answer - if the holes in the emag sear would match what you are dooing, why not see if you can order an emag sear, and not a sear assembly from tom. ^_^

Well that's my last ditch resort. I'm not doing it now because A) I'm not 100% sure it'd work and B) Bluntly, I don't want to spend $55 bucks on it. But I will if need be.

[ShooterJM]

Originally posted by hitech


I am planning on trying this with a classic. The emag sear doesn't line up.

Doesn't line up how? This will be dropped into a custom frame at the end of all this. (Right now it's just in a milled out stock frame).

[hitech]

Originally posted by ShooterJM
Doesn't line up how?...

It is my understanding that the emag sear doesn't line up with the classic/mini mag frame rail. I have been trying to decide what to use for a sear. What are you attempting to use?

[billmi]

Originally posted by 314159
i wonder if a replacement booyah, centerflag,..... sear would work?

The Centerflag fram (and I assume Booyah as well) uses the stock sear.

See you on the field,
-Bill Mills

[ShooterJM]

Originally posted by hitech


It is my understanding that the emag sear doesn't line up with the classic/mini mag frame rail. I have been trying to decide what to use for a sear. What are you attempting to use?

I'm sticking with my original plan at this point. Took the trigger pin off of an old style classic sear and I'm using that. I milled out enough in the grip frame to give me easier and clearer access to the bottom part of the sear and to give the solenoid plunger enough clearence to move. In retrospect I should have chosen the same type of solenoid, but in a push configuration. Brought the sear into work so I'll let you know if I got it to work or will have to do some replanning.

[hitech]

Originally posted by ShooterJM
Took the trigger pin off of an old style classic sear and I'm using that.

Thanks for sharing your ideas. What I don't understand is how you are going to attach the solenoid to the sear. I assume you have the solenoid mounted vertically, or can you make it fit horizontally? If vertical, what are you using for a linkage?

[ShooterJM]

Originally posted by hitech
Thanks for sharing your ideas. What I don't understand is how you are going to attach the solenoid to the sear. I assume you have the solenoid mounted vertically, or can you make it fit horizontally? If vertical, what are you using for a linkage?

Ah. Gotcha. The solenoid is mounted mostly vertical, there is about a 5 degree rotation to the direction of the barrel of the gun. I'm attaching the solenoid plunger directly to the sear. The plunger intself has a slot that is a near perfect fit to the sear width. By drilling hole through the plunger and sear I'll be able to place a pin through them, loc-tite it, and should be good to go.

Any linkege that may become neccesary will be done in brazed aluminum.

If I misunderstood your question somehow let me know.


EDIT: Just discovered my programming cable is a poor fit to my stamp. will have to repostion the pins slightly.

[billmi]

Originally posted by 314159
bill, i took a look at the article on warpig about the basic stamp one.

there are a couple things i don't like:
-you can only make adjustments to the millisecond

That is one of the drawbacks to the Stamp. There are DEFINITELY PICs that will give you more processing horsepower, more memory, and more individual options in what you can do in your software, especially compared to a Basic Stamp (there are also PICs that can give you less, too it depends on which model you choose). By no means is the Stamp the be all end all - it's just a very fast and easy solution for many applications.

Re: the board issue and size issue - the PIC by itself is still is not on a board, and it still needs to be on a board with additional components to drive a paintgun. Yes, there are SMT PICs smaller than the Basic Stamp, but you can't just drop the PIC into the grip of a paintgun and solder wires to it's pins, it has to go on a board (if not, why are all those paintgun manufacturers like AGD, WDP, Generation E, ICD, etc. wasting time and money with putting their chips on boards and adding interface circuitry if a $4 chip can do the job entirely by itself?)

If you're going to talk size you need to compare a PIC on a board to a Basic Stamp (not to mention for rapid proof of concept prototyping appications and one-offs, the time and involvement of fabricating a board).

Yes, it is probably possible to design a control board with an SMT PIC that is smaller than a Basic Stamp to do the same things as a Stamp with a MOSFET and necessary paintgun interface parts mounted on it. However, for an airsmith doing their own work in a one-off type application(i.e. not paying the bucks to have a run of high quality boards done - remember we're talking about a $30 Stamp being "expensive") and etching their own boards, they probably won't be able to make things that small.

Precision board etching is not something typically doable in an airsmith's shop (coarse etching is, but then you can't get as small). Tacking 3-4 parts onto a Basic Stamp with a soldering iron is something that can be done in a typical airsmith's shop. Additionally, board design and etching are more advanced skills posessed by fewer airsmiths than those that can weild a soldering iron. Again - less skilled work and knowledge needed to go the Basic Stamp route, even though it has its limitations compared to building a custom board based around a PIC.

To say - "Look the Stamp is $30, when a $4 PIC will do exactly the same thing and more," is comparing apples to oranges. You need to add board fabrication into the PIC cost (both from a dollars spent and time spent, and availability of skills standpoint). In both cases you need to factor in control circuits (MOSFET or other semiconductor for output controll, tiedown resistors, etc.) that would need to be included in the design of a board for the PIC, or be added onto the Stamp's board. For people lacking the skills to program in an assembler or low level language that is free for the PIC, but able to handle the relatively simpler coding of PBASIC, you need to add the cost of the PICBASIC compiler - 59 pounds which is around $90 US. That needs to be added into the cost as well.

-the way that you have your timing set up, you can't time things concurrently, you start something, skip x many operations, stop someting, move on.....

That is incorrect. There are concurrent timers and I/O running for the trigger input. They aren't running for anything else because the application doesn't require them.

If you wanted to run a concurrent timer for anything else, you'd need to write a different program than the one included in the software in the article. Similarly the code included doesn't do pulse width modulation based motor control, tone generation through a speaker, serial communication with other Basic Stamps, or a lot of other things, because it wasn't needed for the given application.

That software does use the BUTTON function which has concurrent timing and I/O built in. This can make things a LOT easier than having to program the concurrent I/O and timing for the trigger yourself.

This was a problem Brass Eagle had with the Rainmaker S/F board in semi auto mode, and the second generation semi board. Note: The following is my speculation of how their software worked based on how it responded, and when I wrote software based on this model, it had the same problems as the Rainmaker S/F. I have not actually seen their source code.

They didn't check for a trigger release concurrent to the firing and loading cycle. They started at trigger 0, and looped there waiting for the trigger to go to 1. When the trigger went to 1, they went to the firing and loading cycle (close the bolt, hold it closed long enought to fire, open the bolt and wait long enough for the next ball to drop), and then when the firing and loading cycle was finished, they looked at the trigger state again. If it was 1, they waited until it was 0 before accepting a 1 as a new trigger pull (otherwise it would be full auto). Problem was that if you released the trigger and made your next trigger pull during the firing and loading cycle, by the time the program looked at the trigger register, it was at 1, so it never saw the release and wouldn't count the new trigger pull as valid, it thought you hadn't let go of the trigger.

The result was that you could pull the trigger, then start shooting faster and faster, and suddenly, even though you were pulling the trigger just a little bit faster, the Rainmaker would be shooting about 1/2 as often.

Because the PBASIC BUTTON function checks both the timing values (needed to descriminate a bounce from a valid state change) and I/O state concurrently with whatever other code is executing, I avoided that problem entirely with the code in the article. Not having to write the concurrent timing and I/O, simply being able to rely on a PBASIC function for them makes writing the software for a paintgun application much easier.

Of couse the features in my example software (concurrent timing, etc.) are moot to what someone's going to put in their gun. It would be illegal for them to run their gun on my software (see the copyright notices), they'd need to write their own software, and would need to include whatever concurrent or sequential timing their application requires. My code is there to give an introduction to PBASIC, not to power someone else's paintgun (read as liability mitigation).

for a bigger solenoid, you will need a bigger mosfet (not the smaller ones that can operate a mac like valve ), for a bigger mosfet, you will probally need a greater voltage than +5 volts to get it out of the reigon where it acts like a current source, and into the reigon where it acts like a resistor to operate the solenoid, this will require some other fun tricks.

Yes, you do need a bigger MOSFET to drive larger solenoids. You'd also need a speaker and driver circuitry to do signal tones out. You'd also need a keypad to do 10 key data entry. You'd need different circuitry depending on your application.

For driving a solenoid, you have to match the wattage of the MOSFET to what the solenoid draws (or you could run a pair in parallel - I've been there and done that on a prototype board for the company that first filed patent on using a solenoid to actuate a sear - it's not something that would go in a production board, but was fine for a proof of concept prototype). You just need to make sure the MOSFET will trigger on +5v, or use another transistor to control the MOSFET with higher voltage if the chosen MOSFET has a higher trigger voltage.

I don't know how you'd get a MOSFET that acts as a current drain to start functioning as a current source though. I haven't learned that trick yet, I'm not an engineer or a hooker :-)

See you on the field,
-Bill Mills

[billmi]

Originally posted by 314159

(simplification)you don't need a programer, you just need this device to hook it up to your computer to program it. (/simplification)

Hey, I'm most clear when I'm mis-stating the obvious :-) I think I got lost in my own words there.

To clarify the point I was trying to make before I sounded like a goober... :-)

Some of the earlier posts implied that a PIC was a cheaper route to go than a Basic Stamp because the linked PIC programmer kit to interface a PC to the PIC was available for around $6 (as opposed to previous discussion of a Basic Stamp "Developer Station"). The PIC programming interface that was linked in this thread was more complex in terms of electronic components than the interface to do the same thing for a Basic Stamp (since it is solely a connectors and wire, not a connector, wire, circuit board, and additional electronic components.) Thus, using similar materials sourcing, the Stamp's interface would cost less, not the interface for the PIC as was implied.

i need some time to think on this one, don't worry, i am shure that i will come up with a whitty responce

I was sure about to make a witty response that made puns out of those typos, but thought the better of it, because after a couple of attempts, I realized they just weren't funny.

Plus, me making cracks about typos is the pot calling the kettle black :-)

See you on the field,
-Bill Mills

[Gambit22]

Bill, with a Stamp, you have to add the same extra components to drive a solenoid valve.

And nothing's easier than making PCBs using the photoscopic method. I invested about $10 in the chemicals and transparencies and that's it!

[billmi]

Originally posted by Gambit22
Bill, with a Stamp, you have to add the same extra components to drive a solenoid valve.

Exactly, and you need to add them to something - the BOARD. Until you do that, you're comparing a component to a system. It's like saying a VolksWagon is no good, because it costs more and is bulkier than a VolksWagon engine which has all the horsepower you'd get in that VW. It neglects the fact that you have to build a chassis and support hardware to use the engine. Not to mention that amongst the people who have the skills to use the finished car, not all have the skills to build the chassis. For those that do have the skills to build a chassis, it may be a very easy task that seems almost inconsequential.

And nothing's easier than making PCBs using the photoscopic method. I invested about $10 in the chemicals and transparencies and that's it!

What is the photoscopic method? Is it different than standard photo resist etching? I've known quite a few folks (when in college I worked with a number of EE and ME majors) who were very tecnically oriented, but made some pretty poor quality PCBs, despite having very nice equipment and supplies at their disposal.

Then of course it's back to the target audience of that series of articles - an airsmith that has done little to no electronics work before. What's simipler for that person, tacking a single interface component (a MOSFET or a resistor) to a complete board computer, and wiring that to a switch or solenoid, or designing a board computer printed circuit, etching the board, installing it's components, and the interface component and wiring it. For you, there may be nothing simpler than designing and etching the board. I know a few people who've discussed the articles with me for whom that is too complex, but adding a component to the stamp and programming it was do-able for them. I also have gotten feedback from folks for whom even that is too complex. You have to remember, not all of the world is as skilled and intelligent as you are.

See you on the field,
-Bill Mills

[Gambit22]

You can bend the pins of a PIC outwards in the same fashion and attach the external components in the same way. No, we are not comparing apples and oranges here. The PIC is designed to be an independent active electronic component, and so is the Stamp. There are no real differences between the two except the company, Parallax makes their product sound easier to use, when Microchip has their infosheets geared for an expert.
Parallax isn't even denying it, they use PICs in their Stamp.
Here's the schematic:
http://www.parallaxinc.com/downloads...BS2IC_RevF.PDF
And what do you see on the "board"? a PIC, a crystal, an EEPROM, and a voltage reg. Pick the right PIC(no pun intended) and all you will need will be the voltage reg, and you can even make do with a zener diode!

Furthermore, "tacking on" components to the Stamp, isn't exactly the most reliable method of attaching a component, I already said that it can be done with a PIC if you bend the pins outward, but quality-wise it'd be better to make a PCB.

Which brings me to my last point. You need to make a PCB even if you're using a Stamp, where to place the MOSFET, the voltage reg and other things, because attaching them directly via solder won't last long.

Yes, the photoresist is a better word to use, photoscopic method is what the industry uses with fancy machines.

In reality, working with PICs is a lot easier than most people imagine, the key is not to be intimidated by them.

[314159]

i feel kinda bad about taking a cheap shot at bill's programming, i feel a little bad about it now, and i am sorry. i met bill at the doughnut orgy, and he is a pretty nice guy. well there is more than one way to skin a cat, i just like the pic method. there is nothing wrong with the basic stamp, but giving the picmicro a try might make a nice next step .

[JT2002]

wow, ,is seems complex, any suggestion to getting started, im 14 and very interested in messing around building boards for pb guns, any suggestions for getting started are greatly appreciated,
thanks, JT

[Gambit22]

You need to know at least basic electronics. Find a book on that.

[billmi]

314159,
No worries, I didn't see it as a cheap shot at me (or even a cheap shot, for that matter, you were just talking about drawbacks of using a Stamp as a solution). Certainly the limitations of timing delays to the millisecond isn't my fault, I didn't write PBASIC :-) and unless you were familiar with PBASIC, I certainly wouldn't expect you to know the capabilities of the BUTTON command.

I couldn't agree with you more on it being good to learn about how to use PICs. As I'd said before, the Stamp is not well suited for production, use, and not as flexible or capable of as much computing power as designing a custom app circuit using a PIC.

JT2002 - take a peek at these articles:

http://www.warpig.com/paintball/tech...cs/index.shtml
http://www.warpig.com/paintball/tech...er/index.shtml
http://www.warpig.com/paintball/tech...mp/index.shtml

Don't expect to be an electrical engineer after reading them, but I have gotten a few e-mails from people with little to no electronics experience who were able to build Basic Stamp based paintgun control boards after these articles.

Also, I have found this book somewhat handy:
http://www.amazon.com/exec/obidos/AS...997122-6642417

It has its downfalls (typos, mainly) but at least for me, it has quite understandable explanations of electronic theory and components.

See you on the field,
-Bill Mills

[ShooterJM]

Originally posted by billmi


The Centerflag fram (and I assume Booyah as well) uses the stock sear.

See you on the field,
-Bill Mills

Yeah they replace the on/off don't they? Otherwise the solenoid provided can't acutate the sear, too much pressure. Think I'm personally going to go with the Retro on/off pin.

[billmi]

The Centerflag grip frame uses the standard on/off as well. If it doesn't fit properly, they customize the length ot the on/off pin to compensate.

See you on the field,
-Bill Mills

[ShooterJM]

Originally posted by billmi
The Centerflag grip frame uses the standard on/off as well. If it doesn't fit properly, they customize the length ot the on/off pin to compensate.

See you on the field,
-Bill Mills

huh. wonder how they get enough force from a 9 volt soleniod to do that?

[billmi]

Originally posted by ShooterJM


huh. wonder how they get enough force from a 9 volt soleniod to do that?

There's a big fat capacitor inside the grip. I believe they are charging it, and then punching the solenoid with that charge. Theoretically you could even use a cap to capture the charge kicked back out of the solenoid when the field collapses (oddly enoug when you stop putting current into a coil the field colapses, and that generates a small amount of opposing current) and "recycle" it with the next shot, extending battery life.

See you on the field,
-Bill Mills

[ShooterJM]

I was not aware of that. Actually in this whole "make my own electro mag" process I keep encountering things that I hadn't thought of or didn't know!

[billmi]

Yep, going from idea to implimentation is a lot more complex than most folks realize. There are a lot of folks online who have "invented a new gun," but very few who have actually built one.

It takes a fair amount of mechanical energy to do the job of tripping the sear. Not only is Centerflag pulling whatever trick they are pulling (hey, it's that whole hooker analogy again) with the capacitor to just get enough power out of the 9v to trip the sear, but the front and rear movement requirements of the sear are *real* close to the travel limits of that solenoid. AGD went another route - they went with a beefier solenoid that that offers more travel than required to trip the sear, and a much larger power supply (battery) both in terms of voltage and amperage (9v batteries deliver relatively low amperage compared to other batteries, even an AA). Centerflag's aproach means tighter tolerances, and thus a higher chance that something can be out of spec and cause a failure. The payoff they get for taking that higher chance is a more compact and elegant physical package (due to the smaller solenoid and battery).

Another approach you might consider, is using a very small ram to trip the sear, and tripping that ram with low pressure air from an LPR like the Palmer Rock (or a Rainmaker LPR - they are VERY small, and could be mounted on a flat milled into an gas thru foregrip), controlled by a small solenoid valve (Humphries makes some nice valves smaller than Macs) that is controlled by the electronics.

See you on the field,
-Bill Mills

[ShooterJM]

Yeah, I've thought about that. The thing is I know I'm making some simple, stupid mistake somewhere. I'm running 14.4V 26AWG pull tubular solenoid. At pulses it should have enough to actuate the sear. Especially at the distances it needs to move. I have a few more adjustments to make and hopefully it'll work.

And to think this whole project started just because I wanted to try an idea for an electronic trigger. I should have just bought a cheap electronic gun to hack.