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Hello Everybody,
I have build the PICstep v4.0 and having really problems getting it to work.
I have a topic on Pminmo's bulletin board as wel, but i'm hoping you people can help me as well. http://pminmo.com/phpBB2/viewtopic.php?t=182&start=30
I started a page on his wiki as well to collect all the questions and answers I found.
http://pminmo.com/PMinMOwiki/index.php5?title=Picstep
Foto's of my PICstep are in my building log:
http://www.cnczone.com/forums/showth...5552post275552
The problem is that the motor's wont spin. They do enable (LMD's getting hot, and motors not able to turn).
This has got to do something with the PIC?
Who can give me some advice!
I read most of the threads, I think your problem is the resonator you are using, replace it by a quartz crystal or a quartz oscillator chip, I don't know the values of the components, the two capacitors going from the crystal pins to ground should be ceramic disk (Np0) 22 to 27 pf.Originally Posted by Mister H
Last edited by kreutz; 10-25-2007 at 11:42 AM.
Ok thanks for the answer/suggestion.
I'll go and buy the following article tonight:
http://www.okaphone.com/artikel.asp?id=424086
http://www.okaphone.com/artikel.asp?id=455655
[edit] do you know if they have special mounting (+ or - position or something like that?
Just mount them as close to the PIC pins as possible. I am not familiar with the PIC you are using, but make sure to modify the configuration bits for HS crystal mode.
From the datasheet:
"The PIC16F62X can be operated in eight different
oscillator options. The user can program three
configuration bits (FOSC2 thru FOSC0) to select one of
these eight modes:
• LP Low Power Crystal
• XT Crystal/Resonator
• HS High Speed Crystal/Resonator
• ER External Resistor (2 modes)
• INTRC Internal Resistor/Capacitor (2 modes)
• EC External Clock In"
If you are referring to component polarity, no, they don't have any polarity, so you can mount them anyway you want.do you know if they have special mounting (+ or - position or something like that?)
.
Last edited by kreutz; 10-25-2007 at 11:48 AM.
I think that you are right,
I have studied the resonator and the schematic again and the resonator I have only has two legs in stead of 3.
So I think that the person who ordered these parts for me made a little mistake. I think he has ordered the ZTA-20MX in stead of the ZTT-20MX
http://dkc3.digikey.com/PDF/T073/P1287.pdf
This resonator has no connection to the ground.
It looks reasonable that this causes the problem.
On the attached overlay I wil have to connect the resonator to the left and right hole of X1?
If you have a two pin resonator, try adding the two ceramic capacitors first, if it does not work, then replace the resonator by the quartz crystal.
Hmmz.. The more I think about it, the more i'm thinking that I might still have a 3 leg resonator. (I've been at my girlfriends house the last couple of days so I couldn't check what resonator I have)
But I wil check it this evening (12.15 atm over here) and will post it tonight
I have checked the resonator and it was the right one (3 legged)
I have also tried the two capacitors and the crystal, but it still won't work.
Maybe the problem lies with programming the PIC. I really don't know anything about it.
As I described in the Pminmo board, I programmed it in one program and verified it with another one.
The attached screenshots are the ones i made after reading the PIC in the programmer today.
Is anything wrong with this?
The PIC is an PIC16F628A
The programmer I made is this one:
http://members.home.nl/pamali/ludipipo/ludipipo-nl.htm
Info on the PIC is also on that site.
Is there anything that I can do to verify where the fault lies?
When I measure the Voltage on pins 12 and 13, they change sometimes between 0 and 4,9V when I run a program in Mach 3
The motor won't spin, but you can hear it squeaking sometimes.
When I take a look at the lines the cnc has to make, i noticed that (I connected the motor to the x-axis)when the motor had to change from going to the left to going to the right, it made 1 step and then stops. it does it all the times it changes direction from going left to going right (not reversed:S)
I just checked the V2 assembly code and the HS Xtal is being programmed.
It is difficult to troubleshoot the board at a distance, first we must make sure the oscillator is working as intended (20 Mhz), and that requires the use of a frequency meter or an oscilloscope. Then we need to check the inputs to see if it receiving step and direction signals at the PIc i/o pins level. Then, check the PIC outputs to the power chip to see the switching sequence. If we have 20 Mhz signal at the oscillator's pin, we have step and direction inputs OK (within TTL logic levels), but outputs are not, then we need to check the PIC programming.
Ok, that sounds logic.
The problem for me is that i'm a mechanical engineer and I don't have any electronic equipment except for the multimeter.
But I have 3 PICsteps and none of them work, so there must be something fundamentally wrong.
Is it possible to test if the PIC is working correctly by this method?:
http://pminmo.com/troubleshoot.htm together with this:
When I'm running a program on Mach3, i measure that pins 12 and 13 change state sometimes. But I don't know how often it should change state.Posted: Tue Apr 10, 2007 9:23 am Post subject:
--------------------------------------------------------------------------------
By changing the direction pin of the input connector you should see pins 12 and 13 change state. i.e. less than one volt to greater than 3.3V. If it does the PIC is programmed.
_________________
Phil
Too many interests, too many projects, not enough time!!!!!!!!
Always looking for people to sign my guestbook @ http://pminmo.com
email me by using the email button below
Lets take an sequential approach for the troubleshooting.
-First we need to make sure the input signals are being received (with proper TTL levels) from the PC interface.
In order to do the following tests we need to have a common schematics to refer to, the one I am using now is: http://www.fromorbit.com/projects/pi...4_0_schema.pdf
The test circuits on your links could make you reach the wrong conclusions because there is no debouncing on the switches and only one action on the step switch could produce several successive steps at the output or movement in sudden bursts, what makes difficult to see if the PIC is providing the expected outputs. It is better and easier to use Mach3 to produce the pulses, but we don't know yet if the problem is coming from the Mach3 step/direction pins configuration.
Your Mach3 configuration should reflect Step "Active Low" and Direction "Active Low" on the proper pins.
-Disconnect the motors from the power chips. Disconnect VCC cables from CONN2 (A1out, A2out, B1out, B2out)
-Program J1 jumpers for "Full STEP" mode.
-Connect the 5 volts and Ground to the input connector CONN1, as well as the PC Lpt interface cables, and pins 18 to 25 of the LPt port to GND.
You can use your multimeter to test at pin 6 and Pin 7 of the PIC for logic level changes (the other test lead should be connected to pin 6,7,8 of CONN1).
While jogging with Mach3, Measure the voltage at pin 7 of the PIC, less than 0.8 volts is a logic Low, higher than 2.4 volts is a logic High. Voltages in between indicate a problem in the Lpt port.
1-Take a note of the voltage while jogging Forward.
2-Take a note of the voltage while jogging Reverse.
You should have seen a reversal of the logic voltage during the second step.
If everything went OK, reverse the pins on Mach3 configuration (step where direction was and vice-versa), this will make the step pin receive the direction signal while the direction pin receives the step signal. The purpose of this step is to have a controlled logic level at the input that does not change with time, and thus can be accurately measured with the voltmeter, while being able to provide a logic status change by using the forward and reverse keys for the chosen axis, instead of a pulse sequence (step Signal).
-Put your voltmeter probe at pin 6 and repeat steps 1 and 2
You should get two different logic levels like in the prior test. Stop and let me know the results.
For the next set of tests I need you to build the logic probe on Pminmo's troubleshooting guide. Let me know when you are ready.
Regards,
Kreutz.
Ok I will start the tests.
The first time I'm at home is tuesday and i'll do them then.
As for the Logic probe, can I use the logic probe from the Interface board? see page 3 of the following documentation
http://pminmo.com/4axis/4axisBOBdata.pdf
The logic probe from this board is working.
As for connecting the J1 jumpers in Full step mode, is my assumption in the following link ok?
http://pminmo.com/PMinMOwiki/index.php5?title=Picstep
I'll have a look into the jogging function of MAch3. Don't know yet how it works. The setup of MAch 3 is ok atm I thinkBelow the Pull up resistors you can see the possibility to place jumpers. These jumpers set the mode (full,half,1/4 or 1/8) of the PICstep. The modes are set as following (positions from PICstep.jpg):
1/8th: No jumpers
1/4th: Top right to bottom right wired
1/2: Top left to bottom left wired
full: Top left to bottom left wired and Top right to bottom right wired
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