On AKF there are 8 Oleds display, and they can be changed via SysEx midi messages. 
To understand how it work I advise to read the following articles :

[[https://blog.segger.com/decoding-the-akai-fire-part-3/]]

[[https://github.com/TheKikGen/MPC-LiveXplore/wiki/MPC-internal-controller---Midi-aspects]]

Below are more explanation on how it works. 
 

As i understand AKF Oled are 128x32 pixels . 

{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex1.jpg}}

Each bloc of 7 Pixel are encoded on a 8 Bytes ( octets ) string.

Each byte goes from 00 to 7F (00 to 127 ), do not try over 7F, it will freeze your Oled display.

Following is an example of sysex message 

<code>
Display letter A on 2nd oled display 
amidi -phw:0,0,0 -S 'F0 47 7F 40 0B 00 53 02 00 01 00 38 00 3F 7F 73 19 4F 7F 7F 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 F7'
</code> 

<code>
F0 47 7F 40 : header message 
0B : Set Oled Pixel 
00 53 : Message Length 
02 : Oled display number ( going from 0 to 7 on AKF ) 
00 01 : [starty] [endy]  ( first row going to 0 to 1, second row 1 to 2 etc.. )  ( there are 4 rows on AKF ) 
00 38 : [startx] [endx]
00 3F 7F 73 19 4F 7F 7F : message to display. 
00 .... : message continue ( 00 = black/no display ) 
7F : message ending footer
</code>

Below is a template i used to create my sysex message : 

{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex2.jpg}}

Each column on the picture correspond to a column on the oled. 
Each column has 8 pixels as on the oled screen. 


__Example to lit first column__ ( pixel goes from 1 to 8 , from upper to lower )


{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex3.jpg}}


you have to lit pixel 2 to pixel 8 , so i do : 1+2+4+8+10+20+40 = 70 + 15 (15 in hex is F ) => 7F, that's the first Byte. 

you have to lit pixel 1 , and this one is lit with a seconde Byte in the message which is 40.

So the final message will be 7F 40 00 00 00 00 00 00  


__Example to draw the A letter.__ 

{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex4.jpg}}

The first column is Empty ( black) so first Byte is 0 (00) 
 
The second column is shared with pixels belonging to 2nd Byte, and 3rd Byte. 
To lit 3rd pixel to 7th pixel you have to lit 1+2+4+8+10 => 1F , 
To lit 1st and 2nd pixel you have to do it in the 3rd Byte. So it will be 40+20 => 60. 
As we want the horizontal bar from each side of the letter A, we have to add the value 2, so the final value is 62. 
 
Just like this with this 3 Bytes ( 00 1F 62 ) the oled pattern would have been :

{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex5.jpg}}

<code>
amidi -phw:0,0,0 -S 'F0 47 7F 40 0B 00 53 02 00 01 00 38 00 1F 62 00 00 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 F7'
</code>

Then to continue the A, we need to lit the upper of the A (10+20) , and the lower part of right side of the A ( 1+2+4 ) 
so it gives value 37. 
  
Message is then ( 00 1F 62 37 )

{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex6.jpg}}

<code>
amidi -phw:0,0,0 -S 'F0 47 7F 40 0B 00 53 02 00 01 00 38 00 1F 62 37 00 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 F7'
</code>


And to finish we need to lit the upper part of the right side of the A.

{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex7.jpg}}

This is done by adding the 5th Byte to the string , it is 8+10+20+40 => 78 

Message is ( 00 1F 62 37 78 )

We add 00 to the end to fill other column with black 
Final message is ( 00 1F 62 37 78 00 00 00)

<code>
amidi -phw:0,0,0 -S 'F0 47 7F 40 0B 00 53 02 00 01 00 38 00 1F 62 37 78 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0
0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 F7'
</code>

In this example the A is a bit narrowed, but you can use the one from below which is wider : 

Below are some letters i tried to reproduce, i need to finish it ;) 

{{http://dnttalo.cluster029.hosting.ovh.net/Pictures/LCDSysex8.jpg}}


In my message, i dont really compute the  Message Length and endx values.
I have taken values which are enough long to allow confortable filling, but if you do a longer message you have to consider changing it.