Good Robot H-Bridge?

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It was the A on the end that was messing you up. A sufix can indicate version and/or package type. If you are having problems try dropping the prefix and suffix letters.

Are you sill working with a mentor ?

Next week my class/kids will be soldering up their first processor board. After that we start programming. We will explore making sound/music with a PIC. It is easy do. Just a speaker form an old PC driven through a 47 uF cap on any output pin. No ADC, just cycle the pin at the freq required.

From there we will look at PWM to drive LEDs and then apply that to drive motors to move robots.
 
I have no mentor, nobody that knows a lick about electronics, Self taught

I wish there was sombody that knew what they were talking about when it comes to electronics (tear)

The only person I know that knows a tiny bit about it, is just discovering that 9v across a LED makes it pop (another)

Is there anyway you could teach me a bit like a overtheweb tutor thing? (webcam or somthing)

Also, the kids in my robotics class are in there mostly because of the extra cirriculuar credit they get (another tear) They really dont even care hardly, mostly the mentors just tell them what to do while the student obeys their command without thinking

Our badly outdated website (From early 06, Im not on there)

Hell, nobody even knows what makes up an atom, that is how dull my family and friends are. I am going to ask the AP chemistry teacher for a exam for me to do
 
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I may be able to help you out.

In addition to the in-school students I mentor a home schooled student. If I put the assignments on the net the two of you could work on them together, online. I need to speak with her mom to be sure it is OK with her.

PM me and we can talk about the details. I will need to talk with your parents via phone to get permission. This is a must.

For now get out the inchworm and check to see if it is working using Bill's poster.
 
He needs a PIC first, Krumlink get yourself a 16F887 big, 16F886 medium or 16F88 small. That should sum up all the chips you need to start with. The 16F886 has two PWM and is similar to the one I use on the Mongoose. The 18Fxxxx might be a little tricky to start with.
You could even follow the Mongoose schematic for hookup to the SN754410
 
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I was thinking that Krumlink had gotten a sample order from microchip back when he built his inchworm.

If he wants me to tutor him he will need the chips I am using in my class.
 
I have the following (lots of chipz)
5x 16F877A
5x 16F887
3x 16F886
5x 16F88
8x 16F628A
3x 18F4620
3x 18F2550

I have plenty of PIC's to Pic from (ha ha ha)

I will PM you my email, phone and stuff. Make sure you call around 3-7 in Eastern time.
 
You are well armed for PIC work, get a 18F1320 for your Junebug and you can start programming right away.
The 18F is both little tougher and a little easier than a 16F series PIC. The 18F series are packed with features and require very little bank switching (bank switching is common in a 16F PIC and lots of people get stuck up on it)
16F design is over 30yrs old the 16C50 was the first if I recall. Back in the day when RAM & ROM were expensive so every bit added to the price. Great chips, still popular, lots of code and examples available, hundreds of versions available and very low cost.

Start with the 16F88 IMHO, it's the easiest to connect, debug support, built on OSC and not too overwhelming. The 16F628A is also a great chip and a very good replacement for the 16F84 but lack of a built in debugger makes it less desirable in my opinion.

Like you Krumlink I started in electronics, one day in 1976 one of my instructors brought in a home built computer, simple design 256byte RAM, no ROM (you had to key it all in by hand) but I was amazed. I had to build one and I did. It's like "soft" electronics, you're still making circuits but inside the chip and you can change it without solder!
**broken link removed**
My COSMAC Elf 1802 looked almost exactly like this one.
And here's the article
https://incolor.inebraska.com/bill_r/elf/html/elf-1-33.htm
 
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I want to so bad!!!

I am going to play around with H bridges this weekend

NOTE TO ALL!!!!
To debug a H bridge and know how it is working, use a Bicolor LED (2 colors, 2 leads). It is reversable color, and it is really helpful.
 
When I ordered my parts a few weeks ago from Jameco, I also got myself a SN754410 H Bridge Motor Driver. I was looking at the schematic and some example circuits (cannot find the location sorry) and It looks like it can only reverse a motor when it has only one motor hooked up to it. Should I order another one so that I can reverse 2 motors or can you reverse 2 motors with a Single H Bridge Chip?
 
The SN754410 is a quadruple high-current half-H driver designed to provide bidirectional drive currents up to 1 A at voltages from 4.5 V to 36 V.

It takes a full H (2 half's) to drive a single motor. So it will drive two motors.
 
Normally, I'm all for finding an IC that will do the job rather than building a discrete solution. But for motor drivers...I dunno. THose H-bridge ICs always seem so confusing. Maybe because I learned way too much about an H-bridge before using the IC. I just find it simpler to work with a discrete H-bridge (until something fails anyways).
 
3v0 said:
It takes a full H (2 half's) to drive a single motor. So it will drive two motors.
Not to confuse the issue, but if you're thinking creatively...
- A single SN754410 can drive up to four motors, but only in one direction.
- Or to drive a high-current application other than motors (e.g. lots of LEDs, solenoids)
- The chip could also be used to drive three motors, all in both directions, but with compromises in independence and power (still, handy and conservative if, for instance, you want to drive three motors using one chip in applications where only one of the three motors will be operating at any given time).
- As the datasheet indicates, the SN754410 can be used as a stepper motor driver for a single stepper motor (which means both directions, half-stepping if need be).

3v0's right, too. The design of the SN754410 is obviously intended mainly for the purpose of driving one stepper motor (as I mentioned) or two normal motors with independent direction, starting, and stopping control.
 
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