Search found 637 matches

by paul
Mon Jan 19, 2009 3:29 pm
Forum: BBB
Topic: Key differences between BBB and RBBB
Replies: 1
Views: 8302

Re: Key differences between BBB and RBBB

darudude, The differences between RBBB and BBB are really just in the form factors. There are one or two parts not found on the RBBB such as an inductor for the analog ref voltage, and two reverse polarity diodes instead of one, the power system of the BBB is a tad more complex, but the difference i...
by paul
Mon Jan 19, 2009 11:40 am
Forum: RBBB
Topic: L4931
Replies: 3
Views: 5442

Re: L4931

As long as the center is positive on the power supply, it will work fine. You are correct about the regulator - it will only put out around 300 mA so that will limit what you can hook up to the RBBB. A 7805 is not ideal with a 6V supply because it requires about 2.5 V dropout. I've got some 2940's t...
by paul
Sun Jan 11, 2009 5:09 pm
Forum: 8x8 LED board
Topic: 8x8 LED Board Driver
Replies: 1
Views: 6438

Re: 8x8 LED Board Driver

Here are two chips, both available that appear to work - they seem to be pin compatible but I haven't tested either yet. On the todo list though. A6279EA-T Allegro A6276A As to external memory, it certainly can be done. See Lady Ada's Wave shield and just steal the memory part of the circuit (and co...
by paul
Sun Jan 04, 2009 1:59 pm
Forum: Connecting to BBB, RBBB
Topic: Serial Data to / from BBB
Replies: 2
Views: 4796

Re: Serial Data to / from BBB

madbeing, Sorry for the super slow reply. This fell through the cracks, amid holiday fuss. Everything has been really hectic this year. You are correct that baud mismatch is the usual reason for garbled serial output. Are you just sending to serial monitor in Arduino? Did you change the baud rate in...
by paul
Sun Jan 04, 2009 1:51 pm
Forum: BBB
Topic: AnalogRead
Replies: 2
Views: 9134

Re: AnalogRead

Yes the pin numbering is confusing in my opinion. It's one of those things that the Arduino team in service of supposedly making things easy to use. But then as soon as people get a few chops and get past blinking three LED's it turns out to be confusing. The Arduino team didn't ask me about it thou...
by paul
Sun Dec 28, 2008 12:38 pm
Forum: BBB
Topic: PS-504??
Replies: 2
Views: 6083

Re: PS-504??

I'm afraid that part number is long one at All Electronics. The specified model also had a 1.3mm jack too, and we've since switched to 2.1mm unless you have an older board. I'd recommend 1A @ 6V supply if you can find it. Anything with a 2.1mm jack, center positive in the 6-9 range will work fine. A...
by paul
Fri Dec 26, 2008 3:10 pm
Forum: RBBB
Topic: Problem with RBBB/Atmel168
Replies: 4
Views: 6312

Re: Problem with RBBB/Atmel168

jhornbr225, Sorry for your grief. We finally have some new P4 docs that Brian Riley of Wulfden.org did. He and I jointly developed the P4. On another note, I bought a P4 Serial board and a serial cable so I do not have to use USB. There are three rows of 6 pins on the end of the board opposite the D...
by paul
Sun Nov 30, 2008 12:51 pm
Forum: Hardware
Topic: AVcc
Replies: 1
Views: 4629

Re: AVcc

The AVcc pin provides a reference voltage for the A/D converters. The Atmega 168 datasheet is the best place for detailed reference. Their ref design suggests a small inductor to keep high frequency noise off that pin. You might also be interested in the AREF pin (marked "AR" on the BBB) and AREF (i...
by paul
Thu Nov 27, 2008 2:09 pm
Forum: Connecting to BBB, RBBB
Topic: PL2303 Connection
Replies: 5
Views: 10277

Re: PL2303 Connection

Check the (current) P4 docs - the schematic is in there. Beware of the RX / TX labels on the cable header and digital pins - they are reversed. This is not a mistake if you think about it, the cable TX should go to the chip RX and vice versa. Just swap them if you are having trouble. Connect the DTR...
by paul
Tue Nov 25, 2008 10:13 pm
Forum: RBBB
Topic: Linking boards
Replies: 2
Views: 6491

Re: Linking boards

shags199, I think some people have made some progress on a CAN bus - you can check the Arduino forum and also the Exhibition section of my forum for a "MODBUS" implementation. However I think your best bet for interchip communication is asynchronous serial. The Atmega has a USART built in so it rece...
by paul
Tue Nov 25, 2008 10:01 pm
Forum: Connecting to BBB, RBBB
Topic: PL2303 Connection
Replies: 5
Views: 10277

Re: PL2303 Connection

hamletbon, Sorry about the slow reply, there's something not working in my subscription to this topic. System spec 1) BBB Rev D2 (I notice there's no 1M resistor for the resonator, is it the latest circuit?) It's not necessary - turns out most modern microcontrollers have load resistance built in. 2...
by paul
Mon Nov 24, 2008 8:32 am
Forum: Exhibition
Topic: Controlling a SX-150 analog synth with Arduino
Replies: 1
Views: 6280

Re: Controlling a SX-150 analog synth with Arduino

Rock on dude,

This is way cool. An analog synth I could justify buying too!
I think some, non-midi type controls would be fun too. Get away from just those same 12 notes and all, jk

Paul
by paul
Wed Nov 19, 2008 4:38 pm
Forum: Connecting to BBB, RBBB
Topic: Cannot Download Sketch
Replies: 9
Views: 11098

Re: Cannot Download Sketch

Jim, Don't feel bad about this not all the problems are your fault. First the easy issue I forgot you're not using the cable so just try this. Device Manager -> Com Ports -> COM1 -> Port Settings -> Advanced button -> Set RTS On Close Now for the harder part. If you are using the most conventional, ...
by paul
Wed Nov 19, 2008 11:49 am
Forum: Connecting to BBB, RBBB
Topic: Cannot Download Sketch
Replies: 9
Views: 11098

Re: Cannot Download Sketch

Try this:
A: Change this serial port setting: Device Manager -> Com Ports -> USB Serial Port -> Port Settings -> Advanced button -> Set RTS On Close

Also note that the P4 adapter needs to be jumpered straight across for the pin mapping holes.

Write back if that doesn't get it,

Paul
by paul
Mon Nov 10, 2008 9:53 pm
Forum: Development
Topic: Diecimila Interposer
Replies: 4
Views: 9498

Re: Diecimila Interposer

I hear your pain. I'm working on hooking Lady Ada's Wave shield and having to consult the schematic and board diagram.

I'll post the BBB hookup when I'm done.

Paul
by paul
Mon Nov 10, 2008 9:51 pm
Forum: BBB
Topic: Differences in BBB and RBBB
Replies: 4
Views: 11742

Re: Differences in BBB and RBBB

The 1M resistor on older versions of the BBB is a load resistor for the resonator. It shows up in a lot of schematics but the reality is that most contemporary microcontrollers have this built into the internal crystal oscillator pins. I had to go to some work to track this down and finally got an a...
by paul
Mon Nov 10, 2008 9:31 pm
Forum: Hardware
Topic: Resonator vs Crystal
Replies: 2
Views: 5407

Re: Resonator vs Crystal

The accuracy difference between a regulator and a crystal are on the order of .1% for a resonator vs .01% for a crystal. So in timekeeping - a resonator will be accurate to 10 seconds a day and a crystal might be accurate to 1 or 2 seconds a day. What most people don't understand is that neither the...
by paul
Mon Nov 03, 2008 6:57 am
Forum: RBBB
Topic: i destroyed one of the ceramic capacitors
Replies: 3
Views: 5872

test post

test message
by paul
Sun Nov 02, 2008 3:10 pm
Forum: Development
Topic: Diecimila Interposer
Replies: 4
Views: 9498

Re: Diecimila Interposer

I've thought a lot about the form factor thing and I'm designing the tentatively named freeduino pro, that has a Diecimila form factor, no USB chip but the cable header. But also pins for plugging it into the breadboard and an analog block similar to BBB - That end of the Diecimila is sorely lacking...
by paul
Wed Oct 29, 2008 9:06 pm
Forum: RBBB
Topic: i destroyed one of the ceramic capacitors
Replies: 3
Views: 5872

Re: i destroyed one of the ceramic capacitors

Stick in the .01 and forget about it, you'll never know the difference. It's just a decoupling capacitor made to absorb high frequency noise on the power line. It's in series with a 47 ufd capacitor, and the total capacitance of parallel caps adds. So you might ask yourself 47.1 ufd, what's up with ...