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|-
|1.0.0
|15:29, 4 September 2015 (CEST)
|[[Bora_Embedded_Linux_Kit_(BELK)#BELK_software_components|2.2.0]]
|First release
==Physical interfacing==
To interface the display a small adapter board is needed. On BoraEVB side it is connected to JP17 and JP23 headers. On display side it connects to LCD panel through a flat cable that is plugged onto JP3 header.
At this URL TBD [http://www.dave.eu/system/files/area-riservata/BORA_LCD_ADAPTER_Lumineq_el-320.240.36-hb_1.1.0_0.pdf|link] schematics are available for download.
Also the following changes need to be made on BoraEVB in order to provide LCD required power supplies (12V and 5V power supplies):
* remove D12, D13, RP62, RP64
* wire D1.1 to JP23.2
[[File:An-belk-005-01.jpg|700px]]
The TFEL display is driven by a controller implemented in PL that fetches pixel data from frame buffer and periodically refreshes physical screen. The LCD controller system is composed of an AXI VDMA IP and a custom version of the LCD controller (derived from AN-BELK-004 LCD controller) itself. AXI VDMA and the LCD controller provides configuration registers that are mapped in the following address range:
To implement frame buffer, a portion of main SDRAM is used. This area is allocated at runtime by linux frame buffer driver.
Every pixel on the display has 2 possible states, ON (light pixel) or OFF (dark pixel).On In the frame buffer, the memory each pixel is mapped with 8bit for pixelrepresented by 8 bits. A byte of value 0xFF represents a an ON pixel, and all the other values (0xFE down to 0x00) represent a an OFF pixel.
At the following URL this link TBD the Vivado design is available for download: TBD. Please note that, even if this application note is based on BELK 2.2.0, <strike>this design has been implemented with Vivado 2013.4</strike>.
==Enabling frame buffer driver in linux kernel==
To enable frame buffer driver user need to:
* get the pre-built binaries from TBDthis [http://www.dave.eu/system/files/area-riservata/AN-BELK-005-sw.zip|link].
Kernel and device tree can also be build built with the following procedure:
* update Bora kernel repository (as described [[Bora_Embedded_Linux_Kit_(BELK)#Updating_the_repositories_from_BELK_2.1.0_to_BELK_2.2.0|here]])
* checkout ''bora-feat-lcd-support'' branch (using ''git checkout bora-feat-lcd-support'' command)
* build the updated kernel source as usual
Put the binaries on the first (FAT32) partition of your BELK 2.2.0 SD card, overwriting the original one when if needed. Please note that you need the following files:
* boot.bin
* bora.dtb
