Hi,
just new here.
I have the same board, but if i connect it with this pin layout, only the stepper motor of the y-axis move and only into one way.
What i have found out is, that i can move the y-axis in both directions, if i connect pulse on pin2 and direction on pin17.
Are this boards existing with different layouts?
Now this is confusing... I still have no board so I can't test this, but what I would do (as a last option) is to follow the PCB tracks and find out to which TA8435H pin the parallel port pins connects to.Originally Posted by dustpuppy
I am posting the TA8435H chip datasheet attached. I definitely think this is the number one resource for using this Chinese board.
TA8435h schematic
it is hard to detect connection between RS232 and TA8435 because it is a double sided PCB and lots of logic gate between but try this i believe it is similar .
how Strong the motors should be ?
have you tryed NEMA 17,23,34 ?
and do you think this board will do an accurate job
and give me a feed back on the schematic attached pls.
TA8435h schematic
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it is hard to detect connection between RS232 and TA8435 because it is a double sided PCB and lots of logic gate between but try this i believe it is similar .
how Strong the motors should be ?
have you tryed NEMA 17,23,34 ?
and do you think this board will do an accurate job
and give me a feed back on the schematic attached pls.
http://www.cdle.net/bbs/UploadFile/2...1161488426.jpg
I have an other layout found.
http://dustpuppy.250x.com/8435T4V3.pdf
What is the right one?
Is there a software existing, that can search for the pins? Something, that test all combination and u just have to look, if the steppers turn correct and note the pin the software shows. That would be a big help.
i think my schematic is closer because i have seen the Chines talking about NE555, and yours that not got one.
i have seen to many cnc schematic , last one i built it involve Pic 16f84 microcontroller (i base on it)
i think RS232 layout are different it depend on the configuration of the software , but it always pins between 2 and 9 and the relays are 10 to 14
http://www.dpie.com/pcmcia/rs232sync_pinout.gif
I have made a little software, where u can set the bits of the lpt port to low or high.
After pressing ok it set all pins to low, wait 100ns, set the selected pins to high, wait 100ns and then start again and stop after doing this 1000 times. Can i just try this on the board, or will i damage something on the board or the steppers if i set the wrong pins?
If nothing will be damaged, it can help to find the right combination of pins, if i change some code.
The lpt has 24 used pins that will give 16581375 combinations. A bit too much to test all by hand.
no don't take the risk
i tell you a logic way to know
after you recieve the board and try it. configure MACH3 whaen it works , put your board asine and plug 25 Leds to your the rs232 each in series with 10k resistance and the rs232 Grd
it will illuminate as the output get high the 5V
I was looking at using a computer power supply. Has anyone tried this yet? Is it reliable.
http://www.wikihow.com/Convert-a-Com...b-Power-Supply
The problem is that, if you want to go anywere beyond 60 RPM you will need 24V and if you plan to power 4 motors you need 10A.
These computer PS usualy have a very low current rating at the -12V port...
But if you manage to find a PS that provides 24V with 10A it is should work.
RS232 ??? You mean your board uses the serial port instead of parallel?
Are we talking about a different board type or you meant LPT and wrote RS232?
I think the NEMA number only tells you about external dimentions, not related to power.
These boards can provide 24V / 1.5A so, to get the most out of your motor/board combination you should choose a motor that runs at 1.5A.
The first thing though would be to find how much torque and how much speed you need.
The theoritical maximum power the board can deliver per motor is 24 * 1.5 *1.4142 (if you can have 1.5A / phase and two phases on at the same time), that is about 50W. But as these motors tend to be very unefficient, the best way to know the performance is to look at the specifications.
You can play around with your avaliable power in three ways:
1- Choosing the best motor torque/Amp relation
2- Wiring the motor series or parallel
3- Using a pulley to get either more torque or more speed.
The motors I chose is NEMA 23 and give 0.8 N.m when running at 24V / 1.5A / 60 RPM and 0.4 N.m at 24V / 1.5A / 120 RPM.
These motors would be able to go to double that speed at 48V, but unfortunately a driver board capable of driving with 48V would be much more expensive.
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