2022-07-19 03:44 AM
I am trying to operate 480x272 RGB LCD, SDRAM(for graphic memory), flash memory(for log), BLDC motor, wifi, sound, freeRTOS. At first, it was implemented with STM32F767IIT (flash-2MB, ram-512KB). Since there are too many pins connected to SDRAM and LCD, PCB artwork was difficult and a lot of electromagnetic waves were emitted.
If the LCD interface is MIPI-DSI and drives only with SRAM without using SDRAM, the number of pins can be greatly saved. But I'm not sure if I can drive the LCD while running FreeRTOS with 512KB SRAM.
Is there a development board that implements MIPI-DSI LCD? Or is there a suitable solution?
2022-07-19 04:23 AM
Yes, there are e.g. DISCOVERY that contain a MIPI-DSI LCD, e.g. the 32F469IDISCOVERY or the 32F769IDISCOVERY. However, the DISCOVERY are used to test the respective target MCU, so that many additional components (sensors, etc) are already connected, leaving only a few pins free.
Regards
/Peter
2022-07-19 05:57 AM
At a 16-bit colour depth the display will eat half your memory for a single frame. Apt to get tearing.
Perhaps there are some H7 parts better suited? H747 ?
DSI output is just an extension of the LTDC methods used otherwise, but instead of feeding the RGB parallel pins this is serialized over a much higher clocked serial interface. An LVDS clock, and two LVDS data lanes, as I recall.
2022-07-19 05:32 PM
Check STM32U5 and H7 families. Maybe on st.com therr is a board finder with DSI filter.