How to add USB pen data logging
If you want to add USB pen drive data logging to your system the Vinculum VDIP1 USB host controller works really well.
There are a couple of places you can get the board, farnell stock them for £13.94.
There are already some good guides on using the board with an Arduino. I found these two most useful. I recommend reading these to start with to get a good idea of how it all works. I've added a couple of things to increase the functionality and get rid of write errors which are documented below.
Guide 1 - Writing data to Usb Memory Stick – by Nick on the Arduino playground.
Guide 2 – Usb Storage and Arduino – by Sven Steinbauer
Additions
Wait for 'ok' response
The Vinculum board is controlled using DOS commands and so every time you send a command if the command is executed successfully the board sends a “D:\> ” response that indicates its ready for the next command. If you try and send commands faster than the Vinculum board takes to execute them and don't wait until after the Vinculum board has sent the “D:\> ” ready for new command response, I found I would get errors in the data stored and it would sometimes crash.
To solve this the arduino sketch code listens for a response from the Vinculum board after it sends each command, if it receives “D:\> ” which I've called the ok response then it can go on to send the next command. If it receives “No disk” it stops trying to write to a non existent disk and waits until a disk is inserted and the start write button is pressed.
Start/stop write button and led indicator
Just a simple start/stop write button. To start writing you hold the button down for 2s and the led comes on to indicate writing. To stop writing you hold it down again for 2s and the led turns off. If the arduino wait for 'ok' response code receives a 'no disk' response. The led is automatically turned off.
Hardware
Vinculum VDIP1 wiring diagram:
Start/stop push button + led indicator circuit diagram:
Layout suggestions
A piece of stripboard to mount the Vinculum VDIP1.
Start/stop push button + led indicator
Installation example in the home energy monitor main unit
Component list
Here's the full list of the component for the whole house energy monitor, the datalogger board components are the fourth block.
Download OpenOffice: partlist28Jan.ods
Download Exel: partlist28Jan.xls
Arduino software:
The arduino sketch here works with the board independently of any of the other energy monitor hardware and code. It will just write the values set in the variable declaration to the board as an example. If you connect up the measurement electronics its just a matter of inserting the measurement code in to the code below. For the full code for datalogger, measurement, display etc see the home energy monitor documentation page.
- Download the Data logger Arduino sketch
- Compile and upload the Arduino sketch to the Arduino. For a guide on compiling and uploading the sketch to the Arduino have a look here.
- Check your Arduino serial monitor for write status. Once you have pressed the button you should see the following output if its all working correctly:
Started
O D:\>
W D:\>
C D:\>
O D:\>
W D:\>
C D:\>
...
If your getting the above, press the button again to stop writing (you should see "stopped" come up)and check the usb pen to make sure the data is there.
and that's it, you now have usb pen data logging!
I am trying to log this
I am trying to log this sketch onto a usb pen drive:
/* Arduino sketch for Inspeed Vortex windspeed instrument
The anemometer.
=========================================================
ANEMOMETER
=========================================================
This is connected to Arduino ground on one side, and pin 2 (for the
attachInterrupt(0, ...) on the other.
Pin 2 is pulled up, and the reed switch on the anemometer will send
that to ground once per revolution, which will trigger the interrupt.
We count the number of revolutions in 5 seconds, and divide by 5.
One Hz (rev/sec) = 2.5 mph.
*********************************************************************/
#define uint unsigned int
#define ulong unsigned long
#define PIN_ANEMOMETER 2 // Digital 2
// How often we want to calculate wind speed
#define MSECS_CALC_WIND_SPEED 5000
volatile int numRevsAnemometer = 0; // Incremented in the interrupt
ulong nextCalcSpeed; // When we next calc the wind speed
ulong time; // Millis() at each start of loop().
//=======================================================
// Initialize
//=======================================================
void setup() {
Serial.begin(9600);
pinMode(PIN_ANEMOMETER, INPUT);
digitalWrite(PIN_ANEMOMETER, HIGH);
attachInterrupt(0, countAnemometer, FALLING);
nextCalcSpeed = millis() + MSECS_CALC_WIND_SPEED;
}
//=======================================================
// Main loop.
//=======================================================
void loop() {
time = millis();
if (time >= nextCalcSpeed) {
calcWindSpeed();
nextCalcSpeed = time + MSECS_CALC_WIND_SPEED;
}
}
//=======================================================
// Interrupt handler for anemometer. Called each time the reed
// switch triggers (one revolution).
//=======================================================
void countAnemometer() {
numRevsAnemometer++;
}
//=======================================================
// Calculate the wind speed, and send to serial port.
// 1 rev/sec = 2.5 mph
//=======================================================
void calcWindSpeed() {
int x, iSpeed;
// This will produce mph * 10
// (didn't calc right when done as one statement)
long speed = 25000;//2.5 mph * 1000
speed *= numRevsAnemometer;
speed /= MSECS_CALC_WIND_SPEED;
iSpeed = speed; // Need this for formatting below
Serial.print("Wind speed: ");
x = iSpeed / 10;
Serial.print(x);
Serial.print('.');
x = iSpeed % 10;
Serial.print(x);
Serial.print(" mph");
numRevsAnemometer = 0; // Reset counter
}
But I cannot get it working, do you have any advice ?