Telescope drive motors that don't...

[mister_e]

i had a link yesterday on my signature... just to calm down Mr Jackson's PMS i've removed it.

[T.Jackson]

WTF is going on with you Trent? If you have any anger... buy yourself a dog, find friends, consult a psychologist, drop me PM or e-mail directly!

You're absolutely right mister_e, I shouldn't be taking my frustrations out on you, I do apologize. You must understand that I have a lot on my plate at the moment -- the Australian secret service is busting my balls for me to come up with an electronic device to help catch pedophiles. My life depends on this project, they're pushing me real hard for this.

Perhaps you might be able to help me, mister_e -- got any ideas on how to achieve something like this?

[mister_e]

Don't need to catch them... just kill them... a camera and a gun... that's all you need.

Yes i'm a monster.

[skimask]

Don't need to catch them... just kill them... a camera and a gun... that's all you need.

IMO...a knife is more appropriate...but that's just me...

Yes i'm a monster.

I think you are in the majority...therefore...not a monster...

[T.Jackson]

IMO...a knife is more appropriate...but that's just me...

You're a murderer Jeremy?

[precision]

Hi T.Jackson. Why i seeing, your psychology is equal to Ricky Ponting ?

[T.Jackson]

Hi T.Jackson. Why i seeing, your psychology is equal to Ricky Ponting ?

Nah I just studied a book entitled: "101 ways to catch murderers & pedophiles" and the secret services gave me a couple of hundred grand plus a Ferrari and said go and get'em.

[T.Jackson]

No remorse = death penalty.

[Archangel]

You're a murderer Jeremy?

Nawww,I think he prefers a more personal touch, that's all . . .

[T.Jackson]

<img src="http://www.mdoc.state.ms.us/Death%20Row%20Photos/gaschamber.jpg">

[T.Jackson]

Ever wondered what people in jail look like?

<img src="http://www.planet-source-code.com/Upload_PSC/ScreenShots/PIC20077131757311631.JPG" >

[T.Jackson]

If you're a monster get ready to join them, because we're gonna lock'em all up.

[skimask]

You're a murderer Jeremy?

Jeeze man...Give it up!
Get off the bottle or get off the keyboard...
Regardless of which one you pick, when you're done, get off your pedestal!

[skimask]

Nawww,I think he prefers a more personal touch, that's all . . .

There ya go... After all, where's the balls in a drive by?
Get up close and personal...
Let the person at the pointy end know who's holding the other end...

[T.Jackson]

There ya go... After all, where's the balls in a drive by?
Get up close and personal...
Let the person at the pointy end know who's holding the other end...

Do you know what the word "probability" means Jeremy? Probability in the sense of -- is this person capable of doing this. This is the exact first thing the police look for. You have just confessed to probability using emotive language.

This is the emotive part ...

Get up close and personal ... Let the person at the pointy end know who's holding the other end...

[T.Jackson]

Jeeze man...Give it up!
Get off the bottle or get off the keyboard...
Regardless of which one you pick, when you're done, get off your pedestal!

You know that's what the last guy said to me, couple weeks later he was in cuffs, now he's doing 20 to life. Would have been life without parole had he not confessed to police early in the game.

[skimask]

You know that's what the last guy said to me, couple weeks later he was in cuffs, now he's doing 20 to life. Would have been life without parole had he not confessed to police early in the game.

Good for you! I'm happy for you!
Actually, no I'm not...
Glad you helped put a guy away that most likely deserved whatever he/she got...been there, done that myself (still looking over my shoulder a bit since the guy got out a couple years ago)...
Nonetheless...How's the view from up there?

[skimask]

Do you know what the word "probability" means Jeremy? Probability in the sense of -- is this person capable of doing this. This is the exact first thing the police look for. You have just confessed to probability using emotive language.
This is the emotive part ...

Do you know what the word 'pedestal' means Trent?
Pedestal in the sense of - "Get off your pedestal..."
You have placed yourself on a pedestal using the English language.
That was the language part...

To quote a little green guy I saw in a movie once:
"A life...You must get"

[T.Jackson]

Deep breath Jeremy, settle down -- that's about as far as I go, I just expose them and the 101 coppers on this forum take their pick.

Cya.

[malc-c]

OK - did I miss something here.. How the hell did this topic get from discussing telescope drives to discussing the merrits of death row ???

I gather the original poster gave up in the end and purchased a commercial driver. Maybe because the topic went way off topic, maybe as purchasing a ready made alternative to developing his own was the easy option?

[Acetronics2]

did I miss something here.. ?

Hi, Malc

I Think yes ...

To me, Our Friend Trent smokes too much illegals ...

like in the 60's when writers ( Françoise Sagan i.e. ) were smoking mushrooms to try to get some inspiration ...

but do not worry ... He doesn't bite ...

Or , may be , he tried himself a new electronic version of his Electric Chair ( see previous posts )...

Hope he won't try a new "Trentorized" version of the machine used in the film " FLY" ( w . Jeff Goldblum )

...

Alain

[T.Jackson]

but do not worry ... He doesn't bite ...

And that's exactly why I'd never make it as a copper. My nerves are absolutely shocking and I haven't got the stomach for it. My heart goes out to anyone in law enforcement that goes around chasing these guys, I know it would be absolute hell

[Dodgy Geezer]

"...OK - did I miss something here.. How the hell did this topic get from discussing telescope drives to discussing the merrits of death row ???

I gather the original poster gave up in the end and purchased a commercial driver. Maybe because the topic went way off topic, maybe as purchasing a ready made alternative to developing his own was the easy option...."


No, I'm actually just waiting here for the off-topic discussion to die down. I went and purchased a commercial microstepping chip to use instead of the L293D, but I still expect to drive it using a PIC. In fact, I have some more problems now, because I thought PIC assembler was fairly simple, and it turns out not to be!

I am confused by the memory allocation of variables. As far as I can see, a PIC .ASM file comprises a set of memory declarations followed by some commands. Variables are defined by naming them and giving their locations, thus:

VAR1 EQU H'10' ;defines the location H10 as VAR1
VAR2 EQU H'22' ;defines the location H22 as VAR2

and then you can load them:

MOVLW D'5'
MOVWF VAR1 ;puts 5 in VAR1 (location H10)
.
.
MOVLW VAR1 ;puts 5 back in the W Register

and generally play with them. But when I try to alter the program I have, it complains that some of the variables I create are in 'Restricted Memory'. I can't find any way to work out what is legal memory and what isn't. I have tried putting variable in random places until the error goes away, and then I hit the next problem, which seems to be that other processes also write to the memory locations I am using, so every so often my counts jump up by 20 or so. There are several simple tutorials on the web for blinking LEDs, but none seem to cover this sort of problem...

[mister_e]

Welcome back

Which chip you're using right now? For each PIC, there's some dedicated places for the GPR. Look your datasheet under Data Memory Map, and see where you can sit your General Purpose Registers.

[paul borgmeier]

>>MOVLW VAR1 ;puts 5 back in the W Register

I am not sure if it is important to you, but this line puts 16 into W (not 5).

MOVF VAR1, W

would put 5 back into W

[Dodgy Geezer]

Hi, All,

I'm still using the PIC16F627. Thanks to Mister-E for pointing me at the data sheet (all 170 pages!!). I see that the data memory map is in 4 banks (I thought it was 2), and that there is a difference between 'unimplemented data locations' and 'general purpose registers' (which I don't understand). I had been putting my counts in the unimplemented slots, and they seemed to vary when I didn't touch them. Now I am putting them at H'20' onwards.

Where does the actual program code go? There seems to be no indication of this.

Paul has put his finger on one of my problems - I could not (and still can't) understand why MOVLW VAR1 does not put the contents of location VAR1 into the W register. And in my example, where VAR1 is D'5', where does the 16 come from? Is it D'16', or H'16'? But thanks, Paul - I used your recommendation and now my counts have improved considerably...even though I still don't know why!

I will stick with trying to make this motor work - buying a different microstep driver chip has required a different veroboard circuit, so I have been learning circuit design - VERODES is a really easy program to use for this purpose. Once I have cracked the code issues we will have another go at making this scope turn!

[mister_e]

Small and short explanation here...

There's a slight difference between Literal and Registers

MOVLW Move the literal in W.
Literal is a constant, when you're using a variable in there.. it return the constant associated to your variable... it's address
MOVLW .10 will copy 10 (decimal) in W
<hr>
MOVF Move register to x destination (F or W)
Rough explanation... Registers are variable... mean that you can change register value, not their address

MOVF YourVar,W will copy the value of YourVar to W
MOVF PORTB,W read PORTB, and store it to W
<hr>

where does the 16 come from? Is it D'16', or H'16'?

from this line
VAR1 EQU H'10'

10hex = 16 Decimal
<hr>

Where does the actual program code go? There seems to be no indication of this.

go one page before in your datasheet Memory Organization . Your actual code begin a RESET_VECTOR 0x000. You have different block, Program Memory, Data Memory and EEPROM data. Data memory are your PIC register and your GPRs
<hr>
Unimplemented.. you just can't use them.. not much
<hr>
170 pages... well that's one of those small. I have some which have over 700, and some can't be download in one shot... DsPIC are good example... you must download the whole reference family set + the one for your DsPIC... kinda load of reading before getting comfortable with.

Oh well, don't be afraid, those datasheet looks way bigger when you begin.

[Dodgy Geezer]

Oooh..er. That's my reading for the rest of the day!


But I have one question (lots actually, but most will have to wait). You say that:

VAR1 EQU H'10'

makes the variable VAR1 equal to H'10'. I thought it made the memory register at location '10' addressable as VAR1. If EQU is the command for loading initial values of variables, what is the command for locating them at appropriate places in memory?

[Dodgy Geezer]

Aaah - I think I'm getting it now. I have a reasonably working bit of code - though I still need to understand how the switches work. I will try and get a test rig up over the weekend.

Incidentally, the original design for this board had two PICs, driving the two motors which direct the two axes. This was easy, since they do not need to work together. I am now thinking about automatic box pattern searches, which will need two motors to work in tandem.

This will be quite easy if one PIC can signal the other PIC to make its motor take a step. Is there any electrical reason why this should not be arranged by connecting a one of the RB output pins on the first PIC to an RA input pin on the second PIC? Then holding this pin high would be the equivalent of pressing an input button on the second PIC. Or is this not the way to do it...?