Whadda WPI438 User manual

WPI438
0.96 INCH OLED SCREEN WITH I2C FOR ARDUINO®
USER MANUAL

WPI438
V. 01 –22/12/2021 2 ©Velleman nv
USER MANUAL
1. Introduction
To all residents of the European Union
Important environmental information about this product
This symbol on the device or the package indicates that disposal of the device after its lifecycle could
harm the environment. Do not dispose of the unit (or batteries) as unsorted municipal waste; it
should be taken to a specialized company for recycling. This device should be returned to your
distributor or to a local recycling service. Respect the local environmental rules.
If in doubt, contact your local waste disposal authorities.
Thank you for choosing Velleman®! Please read the manual thoroughly before bringing this device into service.
If the device was damaged in transit, do not install or use it and contact your dealer.
2. Safety Instructions
•This device can be used by children aged from 8 years and above, and persons with
reduced physical, sensory or mental capabilities or lack of experience and knowledge if
they have been given supervision or instruction concerning the use of the device in a
safe way and understand the hazards involved. Children shall not play with the device.
Cleaning and user maintenance shall not be made by children without supervision.
•Indoor use only.
Keep away from rain, moisture, splashing and dripping liquids.
3. General Guidelines
•Refer to the Velleman®Service and Quality Warranty on the last pages of this manual.
•Familiarise yourself with the functions of the device before actually using it.
•All modifications of the device are forbidden for safety reasons. Damage caused by user
modifications to the device is not covered by the warranty.
•Only use the device for its intended purpose. Using the device in an unauthorised way
will void the warranty.
•Damage caused by disregard of certain guidelines in this manual is not covered by the
warranty and the dealer will not accept responsibility for any ensuing defects or
problems.
•Nor Velleman nv nor its dealers can be held responsible for any damage (extraordinary,
incidental or indirect) –of any nature (financial, physical…) arising from the possession,
use or failure of this product.
•Due to constant product improvements, the actual product appearance might differ from
the shown images.
•Product images are for illustrative purposes only.
•Do not switch the device on immediately after it has been exposed to changes in
temperature. Protect the device against damage by leaving it switched off until it has
reached room temperature.
•Keep this manual for future reference.
4. What is Arduino®
Arduino®is an open-source prototyping platform based in easy-to-use hardware and software. Arduino®boards
are able to read inputs –light-on sensor, a finger on a button or a Twitter message –and turn it into an output
–activating of a motor, turning on an LED, publishing something online. You can tell your board what to do by
sending a set of instructions to the microcontroller on the board. To do so, you use the Arduino programming
language (based on Wiring) and the Arduino®software IDE (based on Processing).
Surf to www.arduino.cc for more information.

WPI438
V. 01 –22/12/2021 3 ©Velleman nv
5. Overview
WPI438
OLED displays are great in many ways. They use very little power, are bright, easy to read with a large
viewing angle and have high resolution considering their small size.
resolution: 128 x 64 dots
viewing angle: > 160°
working voltage: 3 to 5 V
recommended library: U8glib
interface: I2C
driver: SSD1306
working temperature: -30 °C to 70 °C
OLED colour: blue
I/O level: 3.3-5 V
dimensions: 27 x 27 mm
6. Pin Layout
VCC
3.3-5 V power supply
Gnd
ground
SCL
serial clock line
SDA
serial data line
7. Example
Connection.
Vcc======5V
Gnd======Gnd
SCL======A5
SDA======A4

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Go to the product page on www.velleman.eu and download the U8glib.zip file.
Start the Arduino®IDE and import this library: Sketch →Include Library →Add Zip library.
Once finished, go back to Sketch →Include Library →Manage library’s, and scroll down until you find the
U8glib library. Select this library and tap “Update”. Now you have the latest version with examples.
Go to Files →Examples and scroll down to U8glib. Open the example Graphicstest.
In the sketch “Graphicstest”, several types of displays can be selected. Just “un-comment” the one you need.
For the WPI438 you have to un-comment:
U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NO_ACK); // Display which does not send AC
Compile and upload the sketch to your Arduino®compatible board and enjoy!
The “Graphicstest”sketch with only the correct driver line for VMA438 looks like this:
/*
GraphicsTest.pde
>>> Before compiling: Please remove comment from the constructor of the
>>> connected graphics display (see below).
Universal 8bit Graphics Library, https://github.com/olikraus/u8glib/
Copyright (c) 2012, [email protected]
All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
* Redistributions of source code must retain the above copyright notice, this list
of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright notice, this
list of conditions and the following disclaimer in the documentation and/or other
materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

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#include "U8glib.h"
// setup u8g object, please remove comment from one of the following constructor calls
// IMPORTANT NOTE: The following list is incomplete. The complete list of supported
// devices with all constructor calls is here: https://github.com/olikraus/u8glib/wiki/device
U8GLIB_SSD1306_128X64 u8g(U8G_I2C_OPT_NO_ACK); // Display which does not send AC VMA438 -
Velleman , UN-comment this line as it is now
void u8g_prepare(void) {
u8g.setFont(u8g_font_6x10);
u8g.setFontRefHeightExtendedText();
u8g.setDefaultForegroundColor();
u8g.setFontPosTop();
}
void u8g_box_frame(uint8_t a) {
u8g.drawStr( 0, 0, "drawBox");
u8g.drawBox(5,10,20,10);
u8g.drawBox(10+a,15,30,7);
u8g.drawStr( 0, 30, "drawFrame");
u8g.drawFrame(5,10+30,20,10);
u8g.drawFrame(10+a,15+30,30,7);
}
void u8g_disc_circle(uint8_t a) {
u8g.drawStr( 0, 0, "drawDisc");
u8g.drawDisc(10,18,9);
u8g.drawDisc(24+a,16,7);
u8g.drawStr( 0, 30, "drawCircle");
u8g.drawCircle(10,18+30,9);
u8g.drawCircle(24+a,16+30,7);
}
void u8g_r_frame(uint8_t a) {
u8g.drawStr( 0, 0, "drawRFrame/Box");
u8g.drawRFrame(5, 10,40,30, a+1);
u8g.drawRBox(50, 10,25,40, a+1);
}
void u8g_string(uint8_t a) {
u8g.drawStr(30+a,31, " 0");
u8g.drawStr90(30,31+a, " 90");
u8g.drawStr180(30-a,31, " 180");
u8g.drawStr270(30,31-a, " 270");
}
void u8g_line(uint8_t a) {
u8g.drawStr( 0, 0, "drawLine");
u8g.drawLine(7+a, 10, 40, 55);

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u8g.drawLine(7+a*2, 10, 60, 55);
u8g.drawLine(7+a*3, 10, 80, 55);
u8g.drawLine(7+a*4, 10, 100, 55);
}
void u8g_triangle(uint8_t a) {
uint16_t offset = a;
u8g.drawStr( 0, 0, "drawTriangle");
u8g.drawTriangle(14,7, 45,30, 10,40);
u8g.drawTriangle(14+offset,7-offset, 45+offset,30-offset, 57+offset,10-offset);
u8g.drawTriangle(57+offset*2,10, 45+offset*2,30, 86+offset*2,53);
u8g.drawTriangle(10+offset,40+offset, 45+offset,30+offset, 86+offset,53+offset);
}
void u8g_ascii_1() {
char s[2] = " ";
uint8_t x, y;
u8g.drawStr( 0, 0, "ASCII page 1");
for( y = 0; y < 6; y++ ) {
for( x = 0; x < 16; x++ ) {
s[0] = y*16 + x + 32;
u8g.drawStr(x*7, y*10+10, s);
}
}
}
void u8g_ascii_2() {
char s[2] = " ";
uint8_t x, y;
u8g.drawStr( 0, 0, "ASCII page 2");
for( y = 0; y < 6; y++ ) {
for( x = 0; x < 16; x++ ) {
s[0] = y*16 + x + 160;
u8g.drawStr(x*7, y*10+10, s);
}
}
}
void u8g_extra_page(uint8_t a)
{
if ( u8g.getMode() == U8G_MODE_HICOLOR || u8g.getMode() == U8G_MODE_R3G3B2) {
/* draw background (area is 128x128) */
u8g_uint_t r, g, b;
b = a << 5;
for( g = 0; g < 64; g++ )
{
for( r = 0; r < 64; r++ )
{
u8g.setRGB(r<<2, g<<2, b );
u8g.drawPixel(g, r);
}
}
u8g.setRGB(255,255,255);
u8g.drawStr( 66, 0, "Color Page");
}

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else if ( u8g.getMode() == U8G_MODE_GRAY2BIT )
{
u8g.drawStr( 66, 0, "Gray Level");
u8g.setColorIndex(1);
u8g.drawBox(0, 4, 64, 32);
u8g.drawBox(70, 20, 4, 12);
u8g.setColorIndex(2);
u8g.drawBox(0+1*a, 4+1*a, 64-2*a, 32-2*a);
u8g.drawBox(74, 20, 4, 12);
u8g.setColorIndex(3);
u8g.drawBox(0+2*a, 4+2*a, 64-4*a, 32-4*a);
u8g.drawBox(78, 20, 4, 12);
}
else
{
u8g.drawStr( 0, 12, "setScale2x2");
u8g.setScale2x2();
u8g.drawStr( 0, 6+a, "setScale2x2");
u8g.undoScale();
}
}
uint8_t draw_state = 0;
void draw(void) {
u8g_prepare();
switch(draw_state >> 3) {
case 0: u8g_box_frame(draw_state&7); break;
case 1: u8g_disc_circle(draw_state&7); break;
case 2: u8g_r_frame(draw_state&7); break;
case 3: u8g_string(draw_state&7); break;
case 4: u8g_line(draw_state&7); break;
case 5: u8g_triangle(draw_state&7); break;
case 6: u8g_ascii_1(); break;
case 7: u8g_ascii_2(); break;
case 8: u8g_extra_page(draw_state&7); break;
}
}
void setup(void) {
// flip screen, if required
//u8g.setRot180();
#if defined(ARDUINO)
pinMode(13, OUTPUT);
digitalWrite(13, HIGH);
#endif
}
void loop(void) {
// picture loop
u8g.firstPage();
do {

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draw();
} while( u8g.nextPage() );
// increase the state
draw_state++;
if ( draw_state >= 9*8 )
draw_state = 0;
// rebuild the picture after some delay
//delay(150);
}
8. More Information
Please refer to the WPI438 product page on www.velleman.eu for more information.
Use this device with original accessories only. Velleman nv cannot be held responsible in the event
of damage or injury resulting from (incorrect) use of this device. For more info concerning this
product and the latest version of this manual, please visit our website www.velleman.eu. The
information in this manual is subject to change without prior notice.
© COPYRIGHT NOTICE
The copyright to this manual is owned by Velleman nv. All worldwide rights reserved. No part of this
manual may be copied, reproduced, translated or reduced to any electronic medium or otherwise without the
prior written consent of the copyright holder.