HB25 Not Responding To Signal From Propeller Professional Development Board PPDB

cnelson700

Summary:· Valid pulse time from PPDB to HB25 and no Vout from HB25.

Well I wired up my 12V LiPo and my 12VDC reversable motor to my HB25.· I then plugged my HB25 into my breadboard and gave it a ground and signal from my PPDB.
The motor did not move.··Using·a voltmeter I found that there·was no Vout from the HB25.

I checked the signal from the PPDB with my Oscope and saw that I was sending a valid signal width·(1.1ms, 1.7ms, 1.9ms, etc) but the motor did not move with any of the signal widths that I sent.

Reading other posts, I tried solutions that worked for others (fully charged battery, etc) and double checked my wiring.
http://forums.parallax.com/showthread.php?p=644138

I tried using my own code (valid signal width on the Oscope) and this Obex code from Claude Hertel· http://obex.parallax.com/objects/100/·(valid signal width on the Oscope).

The HB25 did, however,·work with my BS2 in a Board of Education.

Wondering if 5VDC out, like·from my BS2, is required for HB25 logic state change.·
The Propeller in a PPDB has a 3.3V out and that may not be enough voltage to cause the state change in the HB25, but I am not sure.·

Do I need a logic level converter like the sparkfun logic level converter http://www.sparkfun.com/commerce/product_info.php?products_id=8745
http://forums.parallax.com/showthread.php?p=805489

Any suggestions?

Christopher

Chris Savage

How exactly are you connecting the HB-25 to the PPDB and where do the wires connect? Can you take a photo of the connections?

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Chris Savage

Parallax Engineering
·

cnelson700

I have a wire from pin 16 and a wire from ground on the PPDB to a breadboard.

·

From the breadboard, I used the 14inch extension cable http://www.parallax.com/Store/Accessories/CablesConverters/tabid/166/CategoryID/40/List/0/SortField/0/Level/a/ProductID/386/Default.aspx

and·connected pin 16 (signal) to the white wire and the PPDB ground to the black wire.

·

I connected the other end of the 14inch extension cable to the HB25 with the jumper in place.

·



The battery is a 11.1V 3cell LiPo @ 5000 mAh (ThunderPower eXtemeV2 TP5000=3SXV http://www.thunderpowerrc.com/html/extreme-V2.html).

The battery is connected to the HB25 Vin and GND terminals with crimp on ring terminals.

The reversible 12VDC (surplus windshield wiper motor http://www.sciplus.com/singleItem.cfm/terms/16087)·motor is connected to the M1 and M2 with crimp on ring terminals.

Chris Savage

It's hard to tell with such a small picture, but in our second picture it looks like there are two holes between the wires when there should be one. Where are you testing for the signal by the way? Oh, and finally, you need to make sure the PPBD is on first and looking for the HB-25 to power on to init the I/O lines.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Chris Savage

Parallax Engineering
·

cnelson700

Thanks for the reply Chris.
Here are my answers to your questions:
A) In the second picture (breadboard.jpg) there is only 1 hole between the wires.
Here is a MUCH larger closeup.



I am getting my signal from the breadboard (breadboard.jpg) just underneath the extension cable, and I also checked the signal on the pins of the extension cable on the HB-25 end.

I am powering up the PPDB, with my prog in eeprom, at the same time that I am powering up the HB-25.· My prog holds the HB-25 signal output low for 3 seconds before the first pulse.

Do I need to use a sequence like this:
1) power up PPDB
2) wait 1 second
3) output to relay that powers up HB-25
4) wait 1 second
5) send valid signals to HB-25

Is 3.3V a valid pulse amplitude for the HB-25?· The lit has info regarding the pulse timing but not the amplitude, other than "Servo Pulse Input" .

2ms/div on the ancient oscope below





Christopher

cnelson700

I found out what the problem was. The HB25 was malfunctioning. I used my other HB25 and everything worked as designed.

Christopher