NU32: 16x2 LCD - Revision history

Lynch at 11:35, 16 January 2016

2016-01-16T11:35:50Z

2012-02-17T17:58:01Z

Parallel LCD

2012-02-17T17:45:32Z

Parallel LCD

2012-02-17T17:43:55Z

LCD Hookup

2012-02-17T17:43:23Z

LCD Hookup

2012-02-17T17:42:01Z

Parallel LCD

2012-02-17T16:48:31Z

LCD Hookup

2012-02-16T23:44:51Z

LCD Hookup

2012-02-16T23:44:32Z

LCD Hookup

2012-02-16T17:01:12Z

LCD Hookup

← Older revision		Revision as of 11:35, 16 January 2016
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			'''THIS PAGE REFERS TO A PRE-RELEASE VERSION OF THE NU32 PIC32 DEVELOPMENT BOARD. FOR INFORMATION, SAMPLE CODE, AND VIDEOS RELATED TO THE PRODUCTION VERSION (2016 AND LATER), AND TO THE CORRESPONDING BOOK "EMBEDDED COMPUTING AND MECHATRONICS WITH THE PIC32 MICROCONTROLLER," VISIT [[NU32\|THE NU32 PAGE]].'''


	[[Image:NU32_LCD.jpg\|thumb\|300 px\|left]]<br clear=all>		[[Image:NU32_LCD.jpg\|thumb\|300 px\|left]]<br clear=all>

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 The popular HD44780 (and compatible chipsets) can be interfaced to the NU32 PIC32 board using 10 pins for easy character output to an LCD. This can be highly useful in either debugging or generating a more complex user interface for a PIC (or other microcontroller)-based device.
-This implementation of an HD44780 LCD uses 10 I/O on the PIC as output only, so it is not optimized for speed.
+This implementation of an HD44780 LCD uses 10 I/O on the PIC as output, and the code uses fixed delays after sending commands to allow the LCD time to complete the issued command. The RW pin is fixed to ground, but could instead be used to monitor if the LCD is ready for a new command, but this optimization is not implemented in this code.
 Here is the [[Media:LCD16x2_HJ1602A.pdf|datasheet]].

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 This implementation of an HD44780 LCD uses 10 I/O on the PIC as output only, so it is not optimized for speed.
+Here is the [[Media:LCD16x2_HJ1602A.pdf|datasheet]].
 == LCD Hookup ==

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 </table>
-Note: The V0 pin on the LCD sets the contrast of the characters on the LCD. Create a voltage around 1V using a 10k pot between GND and 5V to get a nice contrast, or hook The V0 pin to GND through a 1kOhm resistor, which also seems to work well.
+Note: The V0 pin on the LCD sets the contrast of the characters on the LCD. Create a voltage around 1V using a 10k pot between GND and 5V to get a nice contrast, or hook the V0 pin to GND through a 1kOhm resistor, which also seems to work well.
 If you power the LCD but do not send it any commands, the top row should fill with boxes. Use this to set your contrast and check that your LCD is powered.

@@ Line 32: / Line 32: @@
 </table>
-Note: The V0 pin on the LCD sets the contrast of the characters on the LCD. Create with a voltage around 1V using a 10k pot to get a nice contrast, or hook it to GND through a 1kOhm resistor, which also seems to work well.
+Note: The V0 pin on the LCD sets the contrast of the characters on the LCD. Create a voltage around 1V using a 10k pot between GND and 5V to get a nice contrast, or hook The V0 pin to GND through a 1kOhm resistor, which also seems to work well.
-If you power the LCD but do not send it any commands, the top row should fill with boxes. Use this to set your contrast and check that your LCD works.
+If you power the LCD but do not send it any commands, the top row should fill with boxes. Use this to set your contrast and check that your LCD is powered.
 The NU32 board is based on 3.3V logical outputs, which works fine for most LCDs, but this LCD must be supplied with 5V on VDD.

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 == Parallel LCD ==
-The popular HD44780 (and compatible chipsets) can be interfaced to the NU32 PIC32 board using 11 pins for easy character output to an LCD. This can be highly useful in either debugging or generating a more complex user interface for a PIC (or other microcontroller)-based device.
+The popular HD44780 (and compatible chipsets) can be interfaced to the NU32 PIC32 board using 10 pins for easy character output to an LCD. This can be highly useful in either debugging or generating a more complex user interface for a PIC (or other microcontroller)-based device.
-This implementation of an HD44780 LCD uses 11 I/O on the PIC as output only, so it is not optimized for speed.
+This implementation of an HD44780 LCD uses 10 I/O on the PIC as output only, so it is not optimized for speed.
 == LCD Hookup ==

@@ Line 18: / Line 18: @@
 <tr><td>3 - V0</td><td>~1k resistor to GND (see note)</td></tr>
 <tr><td>4 - RS</td><td>G12</td></tr>
-<tr><td>5 - RW</td><td>G13</td></tr>
+<tr><td>5 - RW</td><td>GND</td></tr>
 <tr><td>6 - E</td><td>G15</td></tr>
 <tr><td>7 - D0</td><td>E0</td></tr>

@@ Line 16: / Line 16: @@
 <tr><td>1 - VSS</td><td>GND</td></tr>
 <tr><td>2 - VDD</td><td>+5V</td></tr>
-<tr><td>3 - V0</td><td>~1k resistor to GND</td></tr>
+<tr><td>3 - V0</td><td>~1k resistor to GND*</td></tr>
 <tr><td>4 - RS</td><td>G12</td></tr>
 <tr><td>5 - RW</td><td>G13</td></tr>
@@ Line 32: / Line 32: @@
 </table>
-The VEE pin on the LCD (labeled 'A') sets the contrast of the characters on the LCD. Create with a voltage around 1V using a 10k pot to get a nice contrast, or hook it to GND through a 1.5kOhm resistor, which also seems to work well.
+*The V0 pin on the LCD sets the contrast of the characters on the LCD. Create with a voltage around 1V using a 10k pot to get a nice contrast, or hook it to GND through a 1kOhm resistor, which also seems to work well.
 If you power the LCD but do not send it any commands, the top row should fill with boxes. Use this to set your contrast and check that your LCD works.