View source for 12.48inch e-Paper Module (B)

{{infobox item|
|name=12.48inch e-Paper (B)
|name2=12.48inch e-Paper Module (B)
|img=[[File:12.48inch-e-Paper-B-3.jpg|400px|{{Amazon_nolink|default={{#ifeq: {{#urlget:amazon|0}}|{{#urlget:Amazon|0}}| default|}}|url=link=https://www.waveshare.com/12.48inch-e-paper-b.htm}}]]
|img2=[[File:12.48inch-e-Paper-Module-B-1.jpg|400px|{{Amazon_nolink|default={{#ifeq: {{#urlget:amazon|0}}|{{#urlget:Amazon|0}}| default|}}|url=link=https://www.waveshare.com/12.48inch-e-paper-module-b.htm}}]]
|category=[[:Category:Modules|e-Paper]]
|brand=Waveshare
|{{#ifeq: {{#urlget:amazon|0}}|{{#urlget:Amazon|0}}| default|}}=display
|website_cn=[http://www.waveshare.net 中文官网]
|website_en=[https://www.waveshare.com/12.48inch-e-paper-module-b.htm Website]
|related={{Product List|OLEDs / LCDs/e-Paper}}
}}
==Introduction==
*Dimension： 12.48inch
*Outline dimension (raw panel)：261.5mm × 211mm × 0.3mm
*Outline dimension (Acrylic case)：280mm x 229.5mm
*Display size：252.98mm × 190.90mm
*Working voltage：3.3V/5V 
*Interface：SPI
*Dot pitch：0.194mm × 0.194mm
*Resolution：1304 x 984
*Display color：Black, white, red
*Grey level：2
*Full refresh time ：16s
*Refresh power ： 82.5mW(typ.) 
*Standby power ：82.5mW(typ.)(almost none)
【Note】：
Refresh time：The data provided is experimental data, the actual time may be a little different.It is normal that the e-Paper blink when full updating.<br />
Power：The power data is experimental data.<br />
==SPI Communication Timing==
[[File:1.54inch-e-paper-manual-1.png|400px]]

Since the ink screen only needs to be displayed, the data cable (MISO) sent from the machine and received by the host is hidden here.
*CS: Slave chip select, when CS is low, the chip is enabled
*DC: data/command control pin, write command when DC=0; write data when DC=1
*SCLK: SPI communication clock
*SDIN: SPI communication master sends, slave receives
*Timing: CPHL=0, CPOL=0 (SPI0)
[Remarks] For specific information about SPI, you can search for information online.<big>

==How do e-Paper display==
As we know, this display uses the SPI interface, however, there are two FPC cables. In fact, the 12.48inch e-Paper is combined by four small e-Paper, therefore, to control the e-Paper, you should use four chip select pin.<br />

*Update essence
It works as below：<br />
[[file:12.48inch e-paper-4part.png]]<br />
We name the four areas as S2, M2, M1 and S1 respectively, in demo codes, we will send data to these four area in order.<br />
The resolution of S2 and M1 are same 648*492, and the resolution of M2 and S1 are the same 656*492.<br />
Combine the four display we get the resolution of 12.48inch e-Paper: 1304*984<br />

*Control principle
They are four display indeed, therefore, we need to control four SPI salves：<br />
Generally, the control pins of e-Paper are MOSI, SCLK, CS and DC<br />
And power and reset pins: VCC, GND, RST<br />
Because e-Paper will flash when updating, there is a busy pin：BUSY<br />
To reduce pins, four displays use the same VCC, GND, MOSI and SCK pins. Every two displays use the same DC and RST pins.<br />
Therefore, there are total 16 pins for controlling the e-Paper:<br />
[[file:12.48inch e-paper-4part2.png]]<br />

*Codes analysis
To control the e-Paper, you should first reset and initialize registers. And then transmit image data to e-Paper and update.<br />
Here we show you how to transmit the image data：<br />
We take Black-white or Red-white image as a monochrome bitmap. One byte stands for 8 pixels.

S2 and M1: There are 648 pixels per raw, It needs 648/8 = 81 bytes. One display has 492 column,totally  have 81 * 492 = 39852 bytes. The same as the M2 and S1: They totally have 40344 per display。<br />
Registers 0x13 and 0x10 are used to control Black-white image data and Red image data transmitting, here we take two-color display as example<br />
{|border=1 style="text-align:center; width:600px"
|-style="background:blue; color:white"
|'''Color'''||'''0x10'''||'''0x13'''
|-
|White||0xFF||0x00
|-
|Black||0x00||0x00
|-
|Red||0xFF/0x00||0xFF
|}
<pre>
void EPD_12in48_Display(const UBYTE *Image)
{
    int x,y;
    //S1 part 648*492
    EPD_S2_SendCommand(0x13);
    for(y = 0; y < 492; y++)
        for(x = 0; x < 81; x++) {
            EPD_S2_SendData(*(Image + (y*163 + x)));
        }

    //M2 part 656*492
    EPD_M2_SendCommand(0x13);
    for(y = 0; y < 492; y++)
        for(x = 81; x < 163; x++) {
            EPD_M2_SendData(*(Image+ (y*163) +x));
        }

    //S1 part 656*492
    EPD_S1_SendCommand(0x13);
    for(y = 492; y < 984; y++)
        for(x = 81; x < 163; x++) {
            EPD_S1_SendData(*(Image+ (y*163) +x));
        }

    //M1 part 648*492
    EPD_M1_SendCommand(0x13);
    for(y = 492; y < 984; y++)
        for(x = 0; x < 81; x++) {
            EPD_M1_SendData(*(Image+ (y*163) +x));
        }
        
    EPD_12in48_TurnOnDisplay();
}
</pre>

{{12.48e-Paper-connecting-settings}}

==Resources==
===Document===
*[https://www.waveshare.com/w/upload/0/00/12.48inch_e-Paper_Module_SchDoc.pdf Schematic]<br>

===Demo codes===
*[https://www.waveshare.com/w/upload/9/93/12.48inch_e-Paper_Module_Code.7z Demo codes (full)]
*[https://www.waveshare.com/w/upload/9/9a/12.48inch_e-Paper_Module_Code_RPI.7z Demo codes (Pi)]
*[https://github.com/waveshare/12.48inch-e-paper Github]

===Datasheet===
*[https://www.waveshare.com/w/upload/9/99/12.48inch_e-paper_%28B%29_Datasheet.pdf 12.48inch e-Paper datasheet]
===Third-Party examples===
*[https://github.com/martinberlin/cale-idf/ A ESP32 project which is shared by Martin]
:'''It is a "ESP-IDF component", you can drive the e-Paper with GFX and Fonts.'''

==FAQ==
{{E-Paper FAQ}}

==Supports==
{{Service00}}