Reading another thread seemed to indicate there is a way for GLCD have access to external SDRAM as a frame buffer. If this is true then is there a way to get external FPGA access as well? Yet the smart configurator does not allow sharing External Bus pins and LCD_DATAn pins. The thought is if external bus is available we could hang some other parallel device there as well.
Is it possible to leverage external SDRAM space with a separate CSn# for an FPGA? We are targeting the RX72n 144 pin package. Reasoning time constraints dictate the need for fast (parallel) FPGA access of captured measurement data to unpack, calculate, and reconfigure before our next acquisition event.
If not possible are there app notes showing how to build GLCD running on external SDRAM frame buffers?
Thanks!
Russ
Reference other thread titled: RX72N External RAM and LCD interfacing
Hello Russell,
From your comments, I can understand that you want to store the GLCDC buffer on the external SDRAM area of the RX72N.
First of all, please check the links below that you will find how to use GLCDC driver with QE for display and also some demo projects:
Application note:
https://www.renesas.com/en/document/apn/rx-family-qe-display-rx-v110-sample-program-rev110?r=1169191
Αvailable projects:
https://www.renesas.com/en/document/scd/rx-family-qe-display-rx-v110-sample-program-sample-code?language=en&r=1169191
If you check the project, you will find a dedicated internal RAM area that is used to store the frame buffer of the graphics driver:
Also, find attached some projects and an application note that describes how to use Smart Configurator software solution that iniltialize and write on the external SDRAM memory area:
https://www.renesas.com/en/document/apn/rx-family-readwrite-operations-sdram-using-sdramc-rev110?language=en&r=1054466
https://www.renesas.com/en/document/scd/rx-family-readwrite-operations-sdram-using-sdramc-rev110-sample-code?language=en&r=1054466
If you check the project for the SDRAM, you will find how it is used to initialize the start and the stop area of the SDRAM οn the main file:
Μy suggestion is to try to create a simple graphics project using internal RAM of the RX72N. After verifying the correct operation of the project, you can try to delete the frame buffer section on the internal RAM and use the SDRAM area. But be sure that firstly you initialize the SDRMAM and after that implementing the glcdc application, for example :
Regards,
AL_Renesas