Programming Device

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tiredengr

New Member
Hi, I'm a newbe and am looking for direction. I manufacture an electronic timer for model aircaft which currently uses a Parallax Basic Stamp. For a new redesign I want to consider other options. It is important for this application that a small and portable device be available for programming new timing sequences in the field (literally). The device now used is a HP 200LX palm top computer operating DOS 5. As the market for these computers (used) is drying up I am looking for alternatives.
Is it possible to operate the PICAXE software on a Palm Pilot or other modern palm type comuter?
This would be used to modify/update the timing sequences. The basic program in the PICAXE would not be changed; only the timing values, i.e. 4.4 seconds vs 4.7 seconds, etc.
Thanks in advance for your help.
tiredengr
 
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Mycroft2152

Senior Member
Tired,

Interesting project. Its always "possible".

Some more info and details would be helpful. timing values? Are you using the Rs-232 interface on the HP.

A link to your website, perhaps.

Myc
 
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BCJKiwi

Senior Member
If only a single variable needs to be changed, could a potentiometer (or a set of plugin resistors) be used to supply an adjustable voltage to an ADC pin. Then the program could be set up to vary the time in response to a change in the voltage supplied to the ADC port - No program change required in the field.

If this would not give a wide enough range, then a config routine using an Sony Remote and an IR receiver could be implemented instead - still no program change required in the field.
 
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Rickharris

Senior Member
The picaxe SMT is so small and light could not a push button interface suffice - You could construct a plug in version even. A simple PB to raise or lower the time with perhaps an LCD to display the set time.
 
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Andres Rodriguez

New Member
If it is what I think it is (a sequence timer for a free flight airplane), he needs to set several different time delays. Engine cut-off, de-thermalizer, rudder setting, etc.
A single push button may not be enough.
 
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tiredengr

New Member
This is tiredengr with more info on this application.
Size and weight are very critical, also power consumption. My timer weighs about 40 grams which includes the Parallax Basic Stamp 1 (chosen for small size), stepper motor driver, PMOS relay, stepper motor with 24:1 reduction gear box, 4 double layer capacitors (no battery), and a face plate assembly which carries the release wires which are controlled by rotation of a sloted disk. Also there is enough structure to allow it to withstand the very high vibration levels of a modern F1C compitition model with engines that turn 35,00 rpm and develope about 1+ hp.

The timer has 6 sequencial timing sequences; the first five are setable in 0.1 second increments up to 25.5 seconds. The last function which comtrols total flight time is programmed in 1 sec. increments out to 65K sec. (16 bits). At the end of each timing sequence the processor turns on the stepper motor driver ans issues a series of 20 pulses to the motor. This advances the notched timer disk 15 degrees and releases a timer arm to activate a function.

The timer also has a RF interface (receiver is separate from timer) which allows the flyer to over ride any timing sequence from the ground. This is a safety device and allows early termination of a flight if there is a problem.

The original Parallax BS1 (Basic Stamp 1) programming software operated under DOS which is a good fit for the HP 200LX palm top. The input levels to the BS1 are not serial port levels but limited to 0 to +5V signals. To solve this problem Parallax chose to use two pins of a parallel port which requires the addition of a PCMCIA II port card into the HP 200LX. A more modern windows version of the software uses a serial port interface through a small serial to 5V level converter supplied by Parallax. (Sorry to be discussing so much Parallax on this site but only want to present the background).

This timer project is about 10 years old and it is about time for a redesign (this Winter) so I am looking for alternatives to the Basic Stamp which would have programming software that would not need to use a computer running DOS or Windows. I would like to use something like a Palm Pilot for programming in the field. If this is possible with the PICAXE software a secondary problem will be getting a PICAXE device in a smaller form facter than a DIP.

I do have some knowledge limitations also. I am a 76 year old mechanical engineer who has just enough electronics and computer skills to sometimes be dangerous. I have taught myself enough Basic programming to get by and feel it would be an easy transition to the PICAXE, but the field programming device is an important issue. As I stated in my earlier post the market for used (ebay) HP 200LX's seem to be drying up.

One of the posters mentioned using a button and a LCD readout for programming. If this could be accomplished with hardware external to the timer (weight consideration) it would be a viable approach. Even two or three external buttons would be OK; time up and down and a thir button to cycle between the six time settings.

Sorry for this long post but hope that you all can help in my quest for a simple, inexpensive, and very portable programming device.

Thanks again,
tiredengr
 
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Mycroft2152

Senior Member
Interesting project. I've never looked into F1A aircraft before.

For a better idea of what Rod is making, here's a link to one of his competitors:

http://w-hobby.com/?p=Digital Free Flight Controller

Manual:

http://w-hobby.com/FF Timer/WH05mp1.htm

(looks like an 18 pin Microchip controller)

There are a lot of possiblilities with today's PICAXE technology. a few buttons for programmng, an infrared link or a serial interface.

"Programming' may be a misnomer, it sounds like you are just sending a set of tiimer commands, rather than what we would call "programmig" a PICAXE chip.

One important question is whether uyou want the timimng sequence to be retained when the power is off.

Myc

Why not post a photo of your current model
 
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Wrenow

Senior Member
Have you looked at the Asus eeePC? All solid state and tiny (a bit larger than a palmtop, though). Best Buy has them in stock in both Linux and WinXP flavors. Might be just the field programmer you are looking for. HO also has a more expensive mini notebook, but, bang for the buck, I am liking the Asus. Don;t have one yet, but was actually considering one for a field programmer myownself.

Cheers,

Wreno
 
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Mycroft2152

Senior Member
Wrenow said:
Have you looked at the Asus eeePC? All solid state and tiny (a bit larger than a palmtop, though). Best Buy has them in stock in both Linux and WinXP flavors. Might be just the field programmer you are looking for. HO also has a more expensive mini notebook, but, bang for the buck, I am liking the Asus. Don;t have one yet, but was actually considering one for a field programmer myownself.

Cheers,

Wreno
Click to expand...
Interesting little machine, but a bit pricey at $400 US.

Palm Z22's are only $90 (new)
 
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Rickharris

Senior Member
Marmitas said:
If it is what I think it is (a sequence timer for a free flight airplane), he needs to set several different time delays. Engine cut-off, de-thermalizer, rudder setting, etc.
A single push button may not be enough.
Click to expand...
Ok having seen the further information I still feel it would be possible to manufacture a field box to set the device.

Eprom would allow maintaining previous settings and a (few) pushbuttons/LCD display and perhaps a POT to set times would suffice.

The SMT picaxes are very small (certainly in comparison to the Basic Stamp 1) and the cost is MUCH lower so allowing the development and sale of the "programmer" without substantially increasing the overall cost.

Is there a better actuator interface 0 Piezo motor for example - lower weight and cost than a small stepper. Something based on pager motors and switches to indicate the next stop point (could just be piano wire).

Muscle wire? (Shape change alloy) could pull round a ratchet to give steps - much lighter although current hungry.

Sounds like a picaxe project (assuming non critical application!)
 
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papaof2

Senior Member
Food for thought -

Many of the newer Palms are USB only and the serial ports on some versions are marginal. The older Palms (IIIxe for example) actually have +/- voltages out the serial pins (instead of the 0/+5 on later versions). (Palm is not just a hobby - I've done some paid development.)

Maybe use a serial interface to the onboard PICAXE and save the settings to an EEPROM? (if both are SMT, it would be very small)
This should allow having multiple saved data sets so a previous data set could be recalled to be used again. Use a plug-in data entry device with a numeric pad and an LCD display (the plug-in data entry/display device would use another PICAXE - but still cheaper than a BS1). Use a line on the plug-in connector to activate the serial receive function of the on-board PICAXE.

John
 
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Wrenow

Senior Member
Mycroft2152 said:
Interesting little machine, but a bit pricey at $400 US.

Palm Z22's are only $90 (new)
Click to expand...
Ah, but the palm Z22's don't run Windows XP, right? How then do you run the Picaxe IDE to do the updates?

Also, does the Z22 have a compatible serial port or (USB port with drivers for a USB to serial cable)?

Granted, you can pick up an older laptop for $150 or less that will fit the bill, but he was talking about a small field programmer like his old palmtop running DOS, but for field reprogramming the Picaxe. This is the closest to what he was looking for that I am aware of.....

Unless there is a palm based IDE I have missed (that would be sweet).

Cheers,

Wreno
 
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Mycroft2152

Senior Member
Wrenow said:
Ah, but the palm Z22's don't run Windows XP, right? How then do you run the Picaxe IDE to do the updates?

Also, does the Z22 have a compatible serial port or (USB port with drivers for a USB to serial cable)?

Granted, you can pick up an older laptop for $150 or less that will fit the bill, but he was talking about a small field programmer like his old palmtop running DOS, but for field reprogramming the Picaxe. This is the closest to what he was looking for that I am aware of.....

Unless there is a palm based IDE I have missed (that would be sweet).

Cheers,

Wreno
Click to expand...
Wrenow,

DUH! You did not read the link to a "competitor's' version, based on a Microchip 18 pin chip. Look at page 11 for Palm Pilot programing. http://w-hobby.com/FF Timer/WH05mp11.htm

It doesn't look like you need to 'reprogram" the chip with ithe IDE. You only need to feed in your timing sequence selections. That's a horse of a different color.

How successful do you really think a commercial product would be that requires a $400 laptop, when the competing products use a $100 Palm?

Myc
 
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tiredengr

New Member
tiredengr responding to yesterdays posts-
First, a picture is worth a thousand words:

The drawing (lower left view) shows the 10mm stepper, gear box, and end view of the four 3Farad double layer capacitors. The view in the upper left shows how the release wires are captured under the notched disk. The wires are released in sequence as each function times out. Upper left also shows the LEMO programming connector with cover.

I really appreciate all of the comments and suggestions.

I think Mycroft has revealed my ignorance in using mproc. I am in fact downloading the complete program with timing updated timing info for each timer update. I have never figured out how to just update the timer input commands. A quick look at the PICAXE manuals seems to address the changing of data files. Could a programmer be developed to change data in 5 or 6 files using a PICAXE?

To answer his ?, yes the data does need to be retained with power off. This is a safety of flight issue; don't want to launch an uncontrolled missile.

Rickharris suggested using a pot to change the timing values. I am assuming this would be a input to an A/D con. which would feed data to the timer data register. (I hope I'm using the correct terms; maybe over my head) It would also be desiable that the programer (or data setting device) could have an LCD to show the timer data. It would be nice if this could also be used to display the timing data in the timer (T1 -T6). Has anything like this been designed that I could look at to get some idea of the complexity?; or could it be done on a Palm Pilot?

He also suggested other motor alternatives. The torque from Piezo motors or pager motors is very limited and would require some sort of gear reduction. The load on the release wires is in the range of many pounds with all of the lines connected; and yes muscle wire is a current hog. By the way, the 10mm steppers are in the $5 range.

Wreno, I will look at the Asus eeePC. was not aware anything this small was available which runs Windows XP; although @ $400 the price is about double
what would be acceptable in my market. A computer user may go for it though. Many of my customers have very limited computer skills. We're mostly all a bunch of old guys.

After all these suggestions, I am visualizing a small box with an LCD screen to display the timing set points (data), a switch to toggle between the T1 thru
T6 inputs, either a pot or up/down switch to change the data, and a couple more switches to download or read data settings???? does this seem feasible? It would also be very important to be able to read the timing commands that are in the timer.
An IR interface also sounds great, no cables or connectors. It would have to be biderectional, though.


Again, I am in over my head, but could a Dumb Terminal (DT) do this job? At one time there was some software that would run on a Palm Pilot to allow it to be used as a DT. Could something like this be used to read and modify the timer commands??

Thank you all for your comments and for continuing my education.

Rod
 
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Mycroft2152

Senior Member
T,

The pictures are very helpful.

IMHO, you are going to be hard pressed to match the value of a Palm. Yes it can be done, but the cost in small quantites may be prohibitive. That is if you plan on many a profit on the handheld unit :)

You descibed the timer functions as:

The timer has 6 sequencial timing sequences; the first five are setable in 0.1 second increments up to 25.5 seconds. The last function which comtrols total flight time is programmed in 1 sec. increments out to 65K sec. (16 bits). At the end of each timing sequence the processor turns on the stepper motor driver ans issues a series of 20 pulses to the motor. This advances the notched timer disk 15 degrees and releases a timer arm to activate a function.

I would be concerned about the 65K seconds (16 bit) setting. PICAXE ADC's are only good to 10 bits. Using 3 buttons (Up-Down-Accept) to set that time could be frustrating.

Papaof2's description of a possible solution is very close to what I would suggest, with the exception of using a PALM Pilot. Yo would be sending the 7 timer values and perhaps
the flight plan number to the PICAXE / memory via serial interface

Myc
 
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Dippy

Moderator
This ASUS eeeeeeePC got me interested.

How do you connect it to PICAXE?
I findthe asus.com website pretty poor and can't see enough info on connectivity.
It mentions ethernt/WiFi. No mntion of USB.
It says Linux Windows XP compatible, not sure what that means. How compatible?
So, what plugholes has it got?
Where can I see this spc?
Looks more like a flash kid's toy if I were being cynical.
 
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BCJKiwi

Senior Member
When replacing the Parallax with the PICAXE, the timer values are stored in eeprom.
The program works from these stored values and only these values need to be changed, not any part of the program in the timer module.

To change those values, include an IR receiver and code in the timer and send the new values to the timer with a Sony remote (all as suggested back in post #3). The downside to this is that there is no feedback.

An LCD module could be incorporated into a self made remote incorporating another PICAXE thus providing the feedback necessary.

To read out the present values, a second IR circuit could be implemented (in the reverse direction).

A simple tact switch could be mounted on the unit to toggle it into and out of programming mode thus saving on power and eliminating issues of unwanted IR action.

With this system, any number can be sent eliminating the issues of READADC sensitivity.
 
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demonicpicaxeguy

Senior Member
Dippy said:
This ASUS eeeeeeePC got me interested.

How do you connect it to PICAXE?
I findthe asus.com website pretty poor and can't see enough info on connectivity.
It mentions ethernt/WiFi. No mntion of USB.
It says Linux Windows XP compatible, not sure what that means. How compatible?
So, what plugholes has it got?
Where can I see this spc?
Looks more like a flash kid's toy if I were being cynical.
Click to expand...
aparently it does have 3 usb ports on it
and it comes with a cd full of the requird xp drivers if you wanted to run xp

i'd be interested to findout what the screen resolution is on it
and how easy it would be to upgrape the solid state storage
 
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Brietech

Senior Member
I would like to suggest the following:

As others have mentioned, you don't actually need to "reprogram" the device, you just need to change some on-board values. The Picaxe chips have non-volatile (i.e. does not get erased when power goes away) memory that can be used to store the timing values.

Write a simple program that will work for a Windows laptop (visual basic would be simple), or find someone to write the software for you (it will be really simple, I promise). Include a single switch on the device that flips it between "programming" and "normal operation" mode. Just include a simple 3-pin header on the device that brings out the 3 serial pins (ground, Rx, and Tx). Use your software and a normal laptop to send a new series of timing values to the device over the serial connection when it is in "programming" mode, and save those into the non-volatile memory. When the device is switched back into "normal operation" mode it will be good to go.

You will only have to add a small switch and a 3-pin header to the device to accomodate all of this.

For many people, bringing a normal laptop is not a big deal, since they already own one. This way they won't have to haul a dedicated device around and it will be cheaper to acquire the system initially as well.
 
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demonicpicaxeguy

Senior Member
Dippy said:
DPG: "apparently"...
Where does the apparently come from?

It certainly looks like it has some plugholes, but the website mentions nothing.
http://uk.asus.com/products.aspx?modelmenu=1&model=2007&l1=24&l2=0&l3=0&l4=0

Perhaps they haven't made one yet. I'll wait for you to buy one first :)
Click to expand...
aparently = http://en.wikipedia.org/wiki/ASUS_Eee_PC

not bad for the price, although if you could get one of the $100 olpc laptop's http://en.wikipedia.org/wiki/OLPC would be an even cheaper option


looking at the two above links, i doubt it will be long before you can purchase a mobile phone with say 50gig of solid state storage running a full blown version windows xp or vista with couple of high speed usb ports on one side giving you the literal pc in your pocket.
 
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Wrenow

Senior Member
Dippy and DPG,

Best Buy carries the Asus EEEPC with Win XP already installed. Seen it. Like it. Want it. Budget busted with other stuff right now (our warship World Championships are coming up in a couple of months) and then my Daughter's wedding (yes Stan, that daughter).

It has 3 USB ports and an SD card slot for extra removeable storage. Yes, that means it can be a data acquisition device with wifi as well. I wanted it with Linux, but strongly lust after it with XP (because of the Picaxe connectivity).

The screen is an 800x480 7" widescreen. The keyboard is usable, but not something you want to write your next novel on. Interestingly, one place it is getting notice is in the music iindustry - as a controller for samplling, midi controller, etc.

My son, the guru, has done a side-by-side with the latest, larger screen, HP that is $100-200 more and has a larger keyboard and screen (and a hard drive). Winner, to him, the Asus - especially for a field programmer.

When I checked the size, it is about like a smallish larger format paperback book. About 6 of my treo 680's, but still tiny. Won't fit in a shirt pocket, but cargo pants, probably so.

Nice thing - for this application, it is not a required purchase if the end user has a laptop or other windows computer to program/reprogram it. But it can be "certified" or even "offered" for those who want it. However, I was not focusing on making it a commercial product, just getting this particular developer a field programmer HE could use.

Another potential use - as a GPS with a bluetooth GPS RX like my Holux. About the right size - and a lot cheaper than the 7" display $1,000 models out there. Would fit nicely on the dash of my particular car, giving almost a heads up display without blocking the view. But I digress, sorry.

All I know so far. Oh, one other thing, Best Buy carries it in both Linux and XP versions for the same price. What is with that????

Cheers,

Wreno
 
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Dippy

Moderator
Excellent. Thanks Wreno.

Can you please buy and try to let me know how good it is?
You've got loads of money and if it isn't quite what you wanted then you can send it to me ;)
 
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Wrenow

Senior Member
Loads of money? Wish it were but true. :confused: One of the main reasons I am into Picaxing is the relative lack of need of that commodity. :)

I do have a laptop from the Win ME era that I finally upgraded to XP last year, but it is a tad old in the tooth. I do use it for Picaxe programming. So I have been looking at the laptops. I really found the Asus eeePC because I was looking for a Linux solution to another problem (MIDI controller for the organ at our church) as I have moved a couple of confusers at work to Linux due to the cost of maintaining Windoze, and like both the cost and concept. But, of course, that does not help with programming the Picaxe (unless you can get Wine or some such to work). When my son mentioned it is available with XP installed, well... I had to physically go look at it. My impression is it is pretty nice.

Cheers,

Wreno
 
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manuka

Senior Member
Even as we speak the Asus 7" EEE has been declared virtually historic, as a larger EEE 901 9" screen version has just arrived. This itself may be quaint when the "Atom" version arrives in a few months.
 
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krypton_john

Senior Member
Hi All,

Just repeating the a previous suggestion that has been buried under crazy talk of Eee PCs and Palms.

The field programming only consists of setting 6 time delays. This is so simple that it is madness to use any sort of computer. Just use the Sony IR remote as discussed and program the unit by pressing the time delays on the IR remote's keypad. Feedback with an led flash as each digit is accepted.

I would have though an 08M could do this job with it's eyes closed and one hand tied behind it's back.

I guess if the programming being wrong could result in the loss of an expensive model, you might want to add a small led 7 segment display to read back the button presses and settings to make it less error prone.

Alternatively you could make your own remote with a keypad, and IR Led and IR receiver, and an 08M and an LCD display. Then you have bidirectional data, and the remote unit could request a dump of the actuator's settings and display them.

Just my NZ$0.02 worth.
 
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Mycroft2152

Senior Member
krypton_john said:
Hi All,

Just repeating the a previous suggestion that has been buried under crazy talk of Eee PCs and Palms.

The field programming only consists of setting 6 time delays. This is so simple that it is madness to use any sort of computer. Just use the Sony IR remote as discussed and program the unit by pressing the time delays on the IR remote's keypad. Feedback with an led flash as each digit is accepted.

I would have though an 08M could do this job with it's eyes closed and one hand tied behind it's back.

I guess if the programming being wrong could result in the loss of an expensive model, you might want to add a small led 7 segment display to read back the button presses and settings to make it less error prone.

Alternatively you could make your own remote with a keypad, and IR Led and IR receiver, and an 08M and an LCD display. Then you have bidirectional data, and the remote unit could request a dump of the actuator's settings and display them.

Just my NZ$0.02 worth.
Click to expand...
The LCD is probably more appropriate, LEDs tend to be washed out in the sunlight.

It all depends on the overall cost. Remember, this is to be a commercial unit, not a one of, hobbyist project. choices made by a hobbyist are totally different than by a manufacturer. The cost to manufacture a second disolay unit can increase the price significantly. It's not just the display, but the box, batteries etc.

The reason for the PALM discussion is that they are commonly available, inexpensive, and pack a lot of capabilities.

If you seach on F1A timers, you will see that both approaches have been used. It is interesting to note that the first timers were based on music box mechanisms.

Myc
 
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Dippy

Moderator
I was told yesterday by someone called Olive at Palm that the Palm mini USB cannot act as Master and would need some complicated (beyond the scope of this forum) and expensive (beyond the wallet of forumites) interfacing to make it work as a device to talk to a serial device such as PICAXE.
This is a real shame as the programming options on the Palm would have made it a real boon. - come back Psion all is forgiven... or maybe this is a job for the Beijing USB company.
 
hippy

hippy

Ex-Staff (retired)
I guess this is what happens when we start brain-storming in public; lots of possible solutions, some digressions, but not really close to a definitive answer. I think that's because there isn't one, just lots of options, and this discussion could go on for ever.

True tiredengr asked for options but time to bring some focus to the discussion.

The original requirements spec is some replacement means of programming which was previously done via a PC handheld under DOS and obvious solutions on offer so far are -

* On-board programmability ( no external device required )
* Laptop / Portable PC
* PDA / Mobile Phone
* Dedicated programming device

Some of those such as PDA and Mobiles may rule themselves out because although cheap and ubiquitous they don't have the connectivity required. Some may be limited to only a subset of available devices. Lack of direct connectivity can be overcome; adding bluetooth, WiFi, and something able to receive and send SMS would allow any GSM phone to be used for programming and reporting.

It's now up to tiredengr to decide on a particular solution to meet market expectations and manufacturing costs.

If I had to make a quick decision, I'd take what exists and just ramp it up to what people have today - Use serial and rewrite the code to run under Windows.

Anything else means a major change to product hardware or software and limits programming to using specific devices. "Everyone has a laptop PC" and if not they can usually get one at a reasonable price. If they want a compact system choose an EEE or Elonex ONE. If there's a particular PDA which can run the software and do the job then that's a bonus.

My view in cases like this is to go for highest commnest denominator ( Laptop PC, Windows ) then let the market argue the case for anything else.
 
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BCJKiwi

Senior Member
Valuable comments Hippy, but... Tiredengr has indicated (post #1 and post#6) that the product is up for redesign so he is up for changes!
 
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krypton_john

Senior Member
How hard would it be to 'do' IRDA data with a Picaxe? If it was feasible then many laptops, PDAs and pocketPCs come into play as the programming device as they can be easily programmed with a simple custom app to read and transmit the timer setup data. This way there's also a more friendly user interface.
 
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marcos.placona

Senior Member
But wouldn't it just work as a simple touch switch? I mean, there's many ways you can do that, and can even do it by infrared, but the main thing is:

None of them will actually reprogram the picaxe, but will trigger an "input", the same as a button would do.

I believe the same rule applies for bluetooth.

The main concern here, is how to have accurate data, and how to make sure that the speed is actually what it need to be.

A LCD (or any display on this category) would do fine to display the information set, as mentioned before.

You can even think about a tx/rx module with a multi-channel transmitter with many buttons. It's a very elegant approach, and shouldn't put much weight on the thing, but then you need to check if the consumption is good for this kind of approach. I've read the whole thread the other day, but can't remember if consumption is an issue in this case.
 
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Mycroft2152

Senior Member
This thread has definitely lost its focus.

The F1A timer project is well described in post #6.

The timer is currently using a BASIC STAMP 1 and a HP 200 to download the settings.

There are size, weight, and power limitations. Not to mention this is to be a low volume commercial product.

I am sure that T would like to sell more than one unit and make a slight profit.

There are other F1A and F!C electronic timers on the market, which have pretty much set the price point for a sale-able unit. It is worth checking these out to get a pspective.

This project breaks down into two parts, the timer and the programmer.

The BS1 can easily be replaced by a PICAXE 18X or perhaps even a 14M or 20M. The power supply must be able to run the timer for the duration of the flight.

The "programmer" needs to set and send the timer settings. It should be small. lightweight and readable in sunlight. The "programmer" may also need to be able to recharge the power supply.

Myc
 
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