Data logging with an EEPROM - Revision history

Lynch: /* Code */

2009-02-16T08:21:50Z

Code

2009-02-13T20:51:18Z

PIC Code

2009-02-13T20:48:41Z

Circuit

2009-02-13T20:48:22Z

Circuit

2009-02-12T19:45:43Z

Example Output

2009-02-12T18:46:19Z

Example Output

2009-02-12T18:46:06Z

2009-02-12T18:45:51Z

2009-02-12T18:43:15Z

2009-02-12T17:27:48Z

Circuit

← Older revision		Revision as of 08:21, 16 February 2009
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	This project consists of two sets of code: code that is downloaded to the PIC to collect and store data to and send data from the EEPROM , and code that is used by Matlab to collect and plot the data. Within our code, we use a delay time is 5 msec since this is the time required to write the data to the EEPROM. We collect 1000 data points in our code. However, the maximum number of data points is 128,000 assuming each data point is a byte. The EEPROM is capable of storing 1024K bits or 128K bytes.		This project consists of two sets of code: code that is downloaded to the PIC to collect and store data to and send data from the EEPROM , and code that is used by Matlab to collect and plot the data. Within our code, we use a delay time of 5 msec since this is the time required to write the data to the EEPROM. We collect 1000 data points in our code. However, the maximum number of data points is 128,000 assuming each data point is a byte. The EEPROM is capable of storing 1024K bits or 128K bytes.

	===PIC Code===		===PIC Code===

@@ Line 104: / Line 104: @@
          for (i=0; i<1000; i++){
          data = read_adc();//Read in data from analog input (In this case it was attached to a function generator)
-         //printf("Hello world. %Lu %Lu\r\n", i, data);
-         //data++;
          seq_write(address, data); // Send data from analog input to write function
          address++; // Increment up the address location on the EEPROM for the next time it writes something

@@ Line 36: / Line 36: @@
-[[Image:Eeprom2.JPG|thumb|300x300 px|left|Circuit Layout]]
+[[Image:Eeprom2.JPG|thumb|300x300 px|center|Circuit Layout]]
-[[Image:eeprom1.jpg|thumb|300x300 px|right|Circuit Layout including PIC]]
+[[Image:eeprom1.jpg|thumb|300x300 px|center|Circuit Layout including PIC]]
 == Code ==

@@ Line 36: / Line 36: @@
-[[Image:Eeprom2.JPG|thumb|300x300 px|center|Circuit Layout]]
+[[Image:Eeprom2.JPG|thumb|300x300 px|left|Circuit Layout]]
-[[Image:eeprom1.jpg|thumb|300x300 px|center|Circuit Layout including PIC]]
+[[Image:eeprom1.jpg|thumb|300x300 px|right|Circuit Layout including PIC]]
 == Code ==

@@ Line 178: / Line 178: @@
 == Example Output ==
-We input a sine wave from the function generator into the analog input of the PIC and sampled the voltages from the sine wave and saved them to the EEPROM. Matlab was then able to retreive the values from the EEPROM and plot the data. The key limitation of this example is the sampling rate of the code. Since it take 3 ms to write each data point to the EEPROM, the sampling rate is therefore 333.33 Hz.
+We input a sine wave from the function generator into the analog input of the PIC and sampled the voltages from the sine wave and saved them to the EEPROM. Matlab was then able to retreive the values from the EEPROM and plot the data. The key limitation of this example is the sampling rate of the code. Since it take 5 ms to write each data point to the EEPROM, the maximum sampling rate is therefore 200 Hz.
 [[Image:Sinusoidal_output_EEPROM.jpg]]

← Older revision		Revision as of 18:46, 12 February 2009
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	[[Serial communication with Matlab]]		[[Serial communication with Matlab]]

	[[Image:Sinusoidal_output_EEPROM.jpg]]

← Older revision		Revision as of 18:45, 12 February 2009
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	[[Serial communication with Matlab]]		[[Serial communication with Matlab]]

			[[Image:Sinusoidal_output_EEPROM.jpg]]

@@ Line 175: / Line 175: @@
  %Plot retrieved data
  plot(x)
+== Example Output ==
+We input a sine wave from the function generator into the analog input of the PIC and sampled the voltages from the sine wave and saved them to the EEPROM. Matlab was then able to retreive the values from the EEPROM and plot the data. The key limitation of this example is the sampling rate of the code. Since it take 3 ms to write each data point to the EEPROM, the sampling rate is therefore 333.33 Hz.
 == Further Reading ==

← Older revision		Revision as of 17:27, 12 February 2009
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	To operate ~~our~~ EEPROM, PIN1 and PIN2, A0 and A1 are set to ground. PIN3, A2 is connected to high for normal operation. PIN4, Vss is used to ground the chip. PIN5, SDA is the serial data line and is connected to RC4 (PIN23) on the PIC. PIN6, SCL is the serial clock line which is connected to RC3 (PIN18) on the PIC. PIN7, WP is the write protect line. For our purposes, we set PIN7 to ground to disable this function and allow us to rewrite our data onto the EEPROM. PIN8, Vcc is connected to high to power the chip.		To operate the EEPROM, PIN1 and PIN2, A0 and A1 are set to ground. PIN3, A2 is connected to high for normal operation. PIN4, Vss is used to ground the chip. PIN5, SDA is the serial data line and is connected to RC4 (PIN23) on the PIC. PIN6, SCL is the serial clock line which is connected to RC3 (PIN18) on the PIC. PIN7, WP is the write protect line. For our purposes, we set PIN7 to ground to disable this function and allow us to rewrite our data onto the EEPROM. PIN8, Vcc is connected to high to power the chip.

	In order to connect our PIC to Matlab, we use the RS232. As mentioned [[PIC RS232\|here]], we connect the black wire to ground, the orange wire to pin 26, RC7 and the yellow wire to pin 25, RC6.		In order to connect our PIC to Matlab, we use the RS232. As mentioned [[PIC RS232\|here]], we connect the black wire to ground, the orange wire to pin 26, RC7 and the yellow wire to pin 25, RC6.