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1  Using Arduino / Programming Questions / Re: CAN WE FLASH ARDUINO REMOTELY??? on: Today at 04:37:18 pm
Quote
because it is obviously non-volatile ram so "flash" is technically the correct term.
Have you read the datasheet raschemmel? There is no non-volatime ram - there is flash memory.

Further, it has a write cycle limit:
Write/Erase Cycles: 10,000 Flash
so it is not ram at all but more a form of eeprom. This App note describes it more.
http://www.atmel.com/images/doc3708.pdf
2  Using Arduino / Programming Questions / Re: CAN WE FLASH ARDUINO REMOTELY??? on: Today at 03:31:11 pm
Quote
All of the answers you have been given pertain to loading a bootloader not uploading sketches.
Not at all true - Xbee on FIO is for uploading sketches, as is the Adafruit Bluetooth. Both only connect to the Serial lines, so they could do nothing else.
Doesn't help to have students reloading bootloaders remotely.
Flash in this case obviously refers to reloading a sketch into Flash memory.
3  Using Arduino / Programming Questions / Re: max7219 en arduino random led on: Today at 02:47:18 pm
Use the random( ) command to pick a number from 0 to 63, then write the appropriate bit into one of 8 registers that represents the state of the 64 LEDs the MAx7219 controls.
4  Using Arduino / Programming Questions / Re: Atmega8 V-Usb TIMSK0 compile error on: Today at 02:38:01 pm
By names, I meant Registers.
5  Using Arduino / Programming Questions / Re: Atmega8 V-Usb TIMSK0 compile error on: Today at 02:34:59 pm
You can check the Atmega8 datasheet here
http://www.atmel.com/products/microcontrollers/avr/megaAVR.aspx
The supported names & instructions are at the end, check to see what the '8 has.
6  Using Arduino / Networking, Protocols, and Devices / Re: Multi-state input on ATMega328p and ATtiny85 on: Today at 02:00:36 pm
Or add a fast external multichannel ADC, such as MCP3208
http://www.digikey.com/product-detail/en/MCP3208-CI%2FP/MCP3208-CI%2FP-ND/305928

Valid inputs read as near 0, near 3.3V (2.3 to 3.3), near 5V (>3.5V).
Have weak resistor divider to hold disconnected voltage in the range of
>1.5V  and < 2.3V,
so it's above 0.3 x Vcc at 3.3V or 5V (0.99 to 1.5V),
and below 0.7 x Vcc at Vcc = 3.3V or 5V (2.31 to 3.5V).
7  Using Arduino / Programming Questions / Re: working with Array (basic code but very strange) on: Today at 01:48:22 pm
Looks like returned size is in bytes, while the arrays are declared as ints.
1 int = 2 bytes
8  Using Arduino / Sensors / Re: Trouble reading SN74HC165N Shift register on: Today at 01:45:52 pm
Change your code a little:
Code:
void loop()
{
  // Sample the parallel input
  digitalWrite(lock, LOW);
  digitalWrite(lock, HIGH);
 
  // Read
  byte b = shiftIn(data, clk, MSBFIRST);
  Serial.println(b);


  delay(2000);
}
Make sure 2 & 15 are connected together.
Make sure to add 0.1uF cap on VCC as suggested earlier.
9  Using Arduino / Networking, Protocols, and Devices / Re: read data from SPI on: Today at 01:35:02 pm
I2C is 100KHz/400KHz, SPI/4 = 4 MHz, likely an issue as well smiley-cool
10  Using Arduino / Networking, Protocols, and Devices / Re: read data from SPI on: Today at 01:34:14 pm
In general, this did not help:
Code:
    SPI.setBitOrder(MSBFIRST);  << needs to go after SPI.begin();
    SPI.setDataMode(SPI_MODE0);  << needs to go after SPI.begin();
    SPI.setClockDivider(SPI_CLOCK_DIV4); << needs to go after SPI.begin();
    SPI.begin();
At the same time, those are the default settings, so likely it didn't really hurt the effort.
Trying to do I2C with SPI pins is not the best.
11  Using Arduino / General Electronics / Re: Driving several MAX7219 (clones) using 7414 buffers. on: Today at 01:25:44 pm
Look at 7414 high level output drive:
Current - Output High, Low 800µA, 16mA
Little bit of capacitance in the wiring will kill your high-going signal.
Try adding 4.7K pullup on its outputs, get those highs pulled up nice & solid.
12  Using Arduino / General Electronics / Re: Driving several MAX7219 (clones) using 7414 buffers. on: Today at 01:23:01 pm
That's a slow chip, adds an awful lot of delay to the clock line.
Try a faster chip, 74AC04,
http://www.digikey.com/product-detail/en/SN74AC04N/296-4290-5-ND/375817

or a part with one gate, no inversion
http://www.digikey.com/product-detail/en/SN74F125N/296-3548-5-ND/373675
Different pinout, but much faster.
13  Using Arduino / Motors, Mechanics, and Power / Re: Stepper motors - how do I find out which wire is which ? on: Today at 01:11:43 pm
Do a little investigating and determine which wire is which:
http://www.reuk.co.uk/Stepper-Motor-Basics.htm

Sanyo CP-062 stepper does not yield much info when googling.
14  Products / Arduino Due / Re: From Arduino board to an Embedded aplication. on: Today at 01:03:10 pm
FT232R, FT232RL (package difference).
15  Products / Arduino Due / Re: From Arduino board to an Embedded aplication. on: Today at 01:02:41 pm
16U2 provides the USB/Serial interface. Can likely use any USB/Serial interface chip you wanted, such as FT2323R or FT232RL.
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