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1  Forum 2005-2010 (read only) / Interfacing / Re: Sparkfun SerLCD on: February 06, 2007, 03:22:10 pm
Yup, that helped.

Turns out the key is to use:   Serial.print(0xFE, BYTE);   In other words sending the hex as 'byte' so that it is transmitted literally.  Looks like all the other .print() formats translate whatever you give them into ASCII.

I've got the LCD humming along now, and will make up a Sparkfun SerLCD specific playground page soon.  Thanks!
2  Forum 2005-2010 (read only) / Interfacing / Sparkfun SerLCD on: February 06, 2007, 01:05:06 pm
Hi all.

I'm trying to interface my arduino with sparkfun's SerLCD chip running one of their 16character lcd panels.

the documentation is here:

I'm hooking the lcd to the NG's tx port, and just sending commands with serial.print()

If i'm reading the documentation right,    Serial.print(0x01, HEX); should clear the screen.  Instead, the screen just prints '1'.  This is a pretty noobish mistake, i'm sure, but what exactly is going on?  does the print() function translate whatever format you send into ASCII before sending it out over the line?

is there any way i can send a literal hex command to this serial device?  According to the sparkfun documentation, if I can send it a 0x01, it will clear the screen.  Somewhere along the line though (i'm suspecting the print() command, it's being translated to a '1'
3  Forum 2005-2010 (read only) / Interfacing / change the serial rx tx pins to 2 and 3 on: January 03, 2007, 12:46:41 am
The sparkfun protoshield has blusmirf headers on it that map its rx/tx pins to pins 3 and 4 on the arduino board.  As far as I have found, the Serial object only transmits on pins 0 and 1.  Is there any way to change that behavior?  I'd like to be able to select the pins to transmit on.

(obviously this can be remedied by changing the wiring, but the board is already stamped, and it'd just be cleaner to change in software..  also, when code is uploaded, it wouldn't be hitting the pins of the bluesmirf which i'm currently jacking into 0 and 1.)

sparkfun's version of the proto shield:

sparkfun's bluesmirf:
4  Forum 2005-2010 (read only) / Interfacing / Re: arduino sized project box? on: November 30, 2006, 07:18:05 pm
cool!  what are you doing with those box projects?  are they general prototyping setups or have you dedicated them to a specific purpose?

I'd like to get mine to fit within a smallish box for temporary projects..  as yet, the lack of definition of those projects has lead to not knowing what size it should be. : )
5  Forum 2005-2010 (read only) / Interfacing / arduino sized project box? on: November 29, 2006, 12:50:03 pm
What kind of project boxes have you all put your arduino boards in?  

It seems like the NG all by itself fits in an altoids tin, but there's not room for much else.

I'd like to find something similar that would have room for at most, the protoshield from sparkfun, with headers and breadboard.  (about 30mm max)

Has anyone come up with a good idea?
6  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: DC power for USB Arduino on: November 17, 2006, 07:08:54 pm
While i've got your brain open for the picking Daniel, I've got another question back on the subject we started on.

So say i've got a 9v source running into the jack.  Can I then safely tap the (i assume unregulated) 9v output on the arduino board to power motors and other high load devices?  Or would i have to go even further up stream and tap it completely external to the ard. board itself?

from what i can see of the traces on the board the 9v port is essentially the same thing as connecting right to the jack.. with the exception of a capacitor or two.
7  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: DC power for USB Arduino on: November 17, 2006, 05:32:15 pm
Quite helpful! Thanks!

How would one go about charging one of those lead acid batts though?  Is it complicated?
8  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: DC power for USB Arduino on: November 17, 2006, 01:56:33 pm
Yeah, i'd love to master the battery problem as well.. I want something that puts out 12v, and enough current to run some other hardware (servos, motors etc) and still be rechargeable.  I've yet to find anything like that...

9  Forum 2005-2010 (read only) / Frequently-Asked Questions / Re: DC power for USB Arduino on: November 15, 2006, 09:18:20 pm
Microprocessors like the Atmel and the PIC do not like power fluctuations. If you draw a lot of current quickly  from your regulated supply, you run the risk of a voltage fulctuation that will disrupt the delicate task of computing going on inside the chip.  The answer is to use lots of filter capacitors to satisfy anything that uses current in 'spikes', to limit by design the current drawn from the microcontroller's power supply, and to never never never never use inductive loads like motors and relays that take their current from the regulated 5V supply.  For those, you want a separate supply, preferablt diurectly from the main DC source.  

I'm a bit confused by the 'never never' use inductive loads like motors.  Does that include steppers?  because I took these instructions:

and made a simple arduino stepper controller.  Did i Just get lucky on amperages and such?  It works just fine on USB..

Along the same lines of the above comments, I've noticed that my own 9v power supply doesn't seem to finish loading programs when i switch it over.  When I check the voltage on the 9v output on the board, I get 8v or so.  I'm assuming this is because my supply's output is 300mA which isn't sufficient?  (I'm an electro-noob as well, so please correct me)
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